how to make an introduction of research

Writing a Research Paper Introduction (with 3 Examples)

Nail your research paper's introduction! Learn to captivate and inform readers from the start—our guide shows how!

Ertugrul Portakal

Apr 12, 2024

TABLE OF CONTENTS

A catchy and informative introduction is essential in academic writing, especially if you want your readers to have background information about your paper. However, writing an interesting and informative introduction can sometimes be a time-consuming and tiring process. If you don't know where to start when crafting an introduction, no need to worry - we've got you covered!

In this article, we will explain step by step what an introduction is in academic writing and how to write it!

Ready? Let's start!

• An introduction is a paragraph that provides information about your entire paper and aims to attract and inform the reader.
• Before writing an introduction or even starting your paper, you need to research academic sources.
• The first one or two sentences of an introduction paragraph should be a hook to attract the reader's attention.
• Afterwards, you need to prepare the reader for your argument by giving background information about your topic.
• Finally, you should state your argument about your topic with a thesis statement.
• If you are writing a longer paper, you can inform your readers about the map of your paper.
• If you are looking for an AI assistant to support you throughout your writing process, TextCortex is designed for you with its advanced features.

What is an Introduction in a research paper?

In any academic writing, including essays and research papers, an introduction is the first paragraph that the reader will encounter. This paragraph should both attract the reader's attention and give them the necessary information about the paper. In any academic paper, the introduction paragraph constitutes 10% of the paper's total word count. For example, if you are preparing a 3,000-word paper, your introduction paragraph should consist of approximately 300 words. You should also write sentences within these 300 words that will attract the reader's attention and provide them with information about the paper.

Importance of an Introduction Paragraph

The biggest function of an introduction paragraph is to prepare the reader for the author's thesis statement. A traditional introduction paragraph begins with a few sentences or questions that will catch the reader's attention. After attracting the reader's attention, necessary background information on the subject is given. Finally, the author explains to the readers what the whole paper is about by stating the thesis. A thesis statement is the final sentence that summarizes the main points of your paper and conveys your claim.

First Things First: Preliminary Research

When working on any academic writing type, it is essential to start by researching your topic thoroughly before beginning to type. What sets academic writing apart from other writing types is the requirement for it to be written using accurate information from reliable sources.

Researching academic sources can be a time-consuming and unnecessary process. One has to read through hundreds of pages, review dozens of articles and verify the accuracy of each source. However, if you're looking to reduce your workload and maximize efficiency by automating repetitive tasks such as literature review, ZenoChat is the perfect solution for you. With its web search feature, ZenoChat can use the entire internet as a data source. Additionally, by activating the "scholar" option of the ZenoChat web search feature, you can ensure that it only uses academic sources when generating output.

How to Create an Introduction for Academic Writing?

Creating an introduction paragraph that is interesting, informative, and conveys your thesis is an easier process than it seems. As long as you have sufficient information about your topic and an outline , you can write engaging introductions by following a few simple steps. Let's take a closer look at how to write an introduction for academic writing.

1-) Start with a Catchy Hook

Your first sentence is one of the factors that most influence a reader's decision to read your paper. This sentence determines the tone of your paper and attracts the reader's attention. For this reason, we recommend that you start your introduction paragraph with a strong and catchy hook sentence.

• Avoid long and complex sentences
• Use clear and concise sentences
• Write a sentence that will spark the reader's curiosity
• You can ask questions that will encourage the reader to read the remaining paragraph
• Avoid fact or overly broad sentences
• Avoid using dictionary definitions as your hook

2-) Give Background Information

After writing a strong hook sentence, you need to provide basic information about your topic so that the reader can understand what they will learn about when they read your paper. In this section, you can benefit from opinions that support or oppose your argument. Additionally, this section should refer to the body paragraphs of your writing.

• You can write a background information sentence for each body paragraph.
• The information here should be concise and compact
• Avoid talking about your evidence and results unless necessary.

3-) State Your Thesis 

After attracting the reader's attention and providing background information, it is time to present your approach and argument towards the topic with a thesis statement. A thesis statement usually comprises one or two sentences and communicates the paper's argument to the reader. A well-written thesis statement should express your stance on the topic.

• Avoid merely stating a fact
• Claim your argument

4-) Tell Reader About Your Paper

Although you need to move on to body paragraphs after the thesis statement in short papers, it will be useful to add a few sentences that will guide the reader in your longer papers. This way, your readers can better understand which arguments they will encounter on which pages and the course of your paper. That leads the reader to clearly understand and follow your content.

Let’s Wrap it Up

Writing an interesting and informative introduction is usually a long process that requires a lot of rewriting. You may need to rewrite a sentence dozens of times so that your words and sentences clearly describe your paper and argument. Fortunately, you can generate state-of-the-art introductions using AI tools and use them with a little editing.

When it comes to text generation, paraphrasing, and grammar & spelling checking, TextCortex is the way to go with its advanced LLMs and customization options. With TextCortex, you can generate all writing types, including introduction, from scratch, rewrite your existing texts, change their tone of voice, or fix their grammar. TextCortex is available as a web application and browser extension. The TextCortex browser extension is integrated with 30,000+ websites and apps. So, you can complete your AI-driven writing tasks anywhere and anytime.

Let's examine a few sample introductions generated by TextCortex.

Example Introduction #1

“Should social media platforms be banned from collecting their users' data?”

Example Introduction #2

“Do electric vehicles decrease overall emissions?”

Example Introduction #3

“Is graffiti an act of vandalism or the creation of art?”

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Home » Research Paper Introduction – Writing Guide and Examples

Research Paper Introduction – Writing Guide and Examples

Table of Contents

Research Paper Introduction

Research paper introduction is the first section of a research paper that provides an overview of the study, its purpose, and the research question (s) or hypothesis (es) being investigated. It typically includes background information about the topic, a review of previous research in the field, and a statement of the research objectives. The introduction is intended to provide the reader with a clear understanding of the research problem, why it is important, and how the study will contribute to existing knowledge in the field. It also sets the tone for the rest of the paper and helps to establish the author’s credibility and expertise on the subject.

How to Write Research Paper Introduction

Writing an introduction for a research paper can be challenging because it sets the tone for the entire paper. Here are some steps to follow to help you write an effective research paper introduction:

• Start with a hook : Begin your introduction with an attention-grabbing statement, a question, or a surprising fact that will make the reader interested in reading further.
• Provide background information: After the hook, provide background information on the topic. This information should give the reader a general idea of what the topic is about and why it is important.
• State the research problem: Clearly state the research problem or question that the paper addresses. This should be done in a concise and straightforward manner.
• State the research objectives: After stating the research problem, clearly state the research objectives. This will give the reader an idea of what the paper aims to achieve.
• Provide a brief overview of the paper: At the end of the introduction, provide a brief overview of the paper. This should include a summary of the main points that will be discussed in the paper.
• Revise and refine: Finally, revise and refine your introduction to ensure that it is clear, concise, and engaging.

Structure of Research Paper Introduction

The following is a typical structure for a research paper introduction:

• Background Information: This section provides an overview of the topic of the research paper, including relevant background information and any previous research that has been done on the topic. It helps to give the reader a sense of the context for the study.
• Problem Statement: This section identifies the specific problem or issue that the research paper is addressing. It should be clear and concise, and it should articulate the gap in knowledge that the study aims to fill.
• Research Question/Hypothesis : This section states the research question or hypothesis that the study aims to answer. It should be specific and focused, and it should clearly connect to the problem statement.
• Significance of the Study: This section explains why the research is important and what the potential implications of the study are. It should highlight the contribution that the research makes to the field.
• Methodology: This section describes the research methods that were used to conduct the study. It should be detailed enough to allow the reader to understand how the study was conducted and to evaluate the validity of the results.
• Organization of the Paper : This section provides a brief overview of the structure of the research paper. It should give the reader a sense of what to expect in each section of the paper.

Research Paper Introduction Examples

Research Paper Introduction Examples could be:

Example 1: In recent years, the use of artificial intelligence (AI) has become increasingly prevalent in various industries, including healthcare. AI algorithms are being developed to assist with medical diagnoses, treatment recommendations, and patient monitoring. However, as the use of AI in healthcare grows, ethical concerns regarding privacy, bias, and accountability have emerged. This paper aims to explore the ethical implications of AI in healthcare and propose recommendations for addressing these concerns.

Example 2: Climate change is one of the most pressing issues facing our planet today. The increasing concentration of greenhouse gases in the atmosphere has resulted in rising temperatures, changing weather patterns, and other environmental impacts. In this paper, we will review the scientific evidence on climate change, discuss the potential consequences of inaction, and propose solutions for mitigating its effects.

Example 3: The rise of social media has transformed the way we communicate and interact with each other. While social media platforms offer many benefits, including increased connectivity and access to information, they also present numerous challenges. In this paper, we will examine the impact of social media on mental health, privacy, and democracy, and propose solutions for addressing these issues.

Example 4: The use of renewable energy sources has become increasingly important in the face of climate change and environmental degradation. While renewable energy technologies offer many benefits, including reduced greenhouse gas emissions and energy independence, they also present numerous challenges. In this paper, we will assess the current state of renewable energy technology, discuss the economic and political barriers to its adoption, and propose solutions for promoting the widespread use of renewable energy.

Purpose of Research Paper Introduction

The introduction section of a research paper serves several important purposes, including:

• Providing context: The introduction should give readers a general understanding of the topic, including its background, significance, and relevance to the field.
• Presenting the research question or problem: The introduction should clearly state the research question or problem that the paper aims to address. This helps readers understand the purpose of the study and what the author hopes to accomplish.
• Reviewing the literature: The introduction should summarize the current state of knowledge on the topic, highlighting the gaps and limitations in existing research. This shows readers why the study is important and necessary.
• Outlining the scope and objectives of the study: The introduction should describe the scope and objectives of the study, including what aspects of the topic will be covered, what data will be collected, and what methods will be used.
• Previewing the main findings and conclusions : The introduction should provide a brief overview of the main findings and conclusions that the study will present. This helps readers anticipate what they can expect to learn from the paper.

When to Write Research Paper Introduction

The introduction of a research paper is typically written after the research has been conducted and the data has been analyzed. This is because the introduction should provide an overview of the research problem, the purpose of the study, and the research questions or hypotheses that will be investigated.

Once you have a clear understanding of the research problem and the questions that you want to explore, you can begin to write the introduction. It’s important to keep in mind that the introduction should be written in a way that engages the reader and provides a clear rationale for the study. It should also provide context for the research by reviewing relevant literature and explaining how the study fits into the larger field of research.

Advantages of Research Paper Introduction

The introduction of a research paper has several advantages, including:

• Establishing the purpose of the research: The introduction provides an overview of the research problem, question, or hypothesis, and the objectives of the study. This helps to clarify the purpose of the research and provide a roadmap for the reader to follow.
• Providing background information: The introduction also provides background information on the topic, including a review of relevant literature and research. This helps the reader understand the context of the study and how it fits into the broader field of research.
• Demonstrating the significance of the research: The introduction also explains why the research is important and relevant. This helps the reader understand the value of the study and why it is worth reading.
• Setting expectations: The introduction sets the tone for the rest of the paper and prepares the reader for what is to come. This helps the reader understand what to expect and how to approach the paper.
• Grabbing the reader’s attention: A well-written introduction can grab the reader’s attention and make them interested in reading further. This is important because it can help to keep the reader engaged and motivated to read the rest of the paper.
• Creating a strong first impression: The introduction is the first part of the research paper that the reader will see, and it can create a strong first impression. A well-written introduction can make the reader more likely to take the research seriously and view it as credible.
• Establishing the author’s credibility: The introduction can also establish the author’s credibility as a researcher. By providing a clear and thorough overview of the research problem and relevant literature, the author can demonstrate their expertise and knowledge in the field.
• Providing a structure for the paper: The introduction can also provide a structure for the rest of the paper. By outlining the main sections and sub-sections of the paper, the introduction can help the reader navigate the paper and find the information they are looking for.

About the author

Muhammad Hassan

Researcher, Academic Writer, Web developer

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How to Write an Introduction for a Research Paper

Table of Contents

Writing an introduction for a research paper is a critical element of your paper, but it can seem challenging to encapsulate enormous amount of information into a concise form. The introduction of your research paper sets the tone for your research and provides the context for your study. In this article, we will guide you through the process of writing an effective introduction that grabs the reader's attention and captures the essence of your research paper.

Understanding the Purpose of a Research Paper Introduction

The introduction acts as a road map for your research paper, guiding the reader through the main ideas and arguments. The purpose of the introduction is to present your research topic to the readers and provide a rationale for why your study is relevant. It helps the reader locate your research and its relevance in the broader field of related scientific explorations. Additionally, the introduction should inform the reader about the objectives and scope of your study, giving them an overview of what to expect in the paper. By including a comprehensive introduction, you establish your credibility as an author and convince the reader that your research is worth their time and attention.

Key Elements to Include in Your Introduction

When writing your research paper introduction, there are several key elements you should include to ensure it is comprehensive and informative.

• A hook or attention-grabbing statement to capture the reader's interest.  It can be a thought-provoking question, a surprising statistic, or a compelling anecdote that relates to your research topic.
• A brief overview of the research topic and its significance. By highlighting the gap in existing knowledge or the problem your research aims to address, you create a compelling case for the relevance of your study.
• A clear research question or problem statement. This serves as the foundation of your research and guides the reader in understanding the unique focus of your study. It should be concise, specific, and clearly articulated.
• An outline of the paper's structure and main arguments, to help the readers navigate through the paper with ease.

Preparing to Write Your Introduction

Before diving into writing your introduction, it is essential to prepare adequately. This involves 3 important steps:

• Conducting Preliminary Research: Immerse yourself in the existing literature to develop a clear research question and position your study within the academic discourse.
• Identifying Your Thesis Statement: Define a specific, focused, and debatable thesis statement, serving as a roadmap for your paper.
• Considering Broader Context: Reflect on the significance of your research within your field, understanding its potential impact and contribution.

By engaging in these preparatory steps, you can ensure that your introduction is well-informed, focused, and sets the stage for a compelling research paper.

Structuring Your Introduction

Now that you have prepared yourself to tackle the introduction, it's time to structure it effectively. A well-structured introduction will engage the reader from the beginning and provide a logical flow to your research paper.

Starting with a Hook

Begin your introduction with an attention-grabbing hook that captivates the reader's interest. This hook serves as a way to make your introduction more engaging and compelling. For example, if you are writing a research paper on the impact of climate change on biodiversity, you could start your introduction with a statistic about the number of species that have gone extinct due to climate change. This will immediately grab the reader's attention and make them realize the urgency and importance of the topic.

Introducing Your Topic

Provide a brief overview, which should give the reader a general understanding of the subject matter and its significance. Explain the importance of the topic and its relevance to the field. This will help the reader understand why your research is significant and why they should continue reading. Continuing with the example of climate change and biodiversity, you could explain how climate change is one of the greatest threats to global biodiversity, how it affects ecosystems, and the potential consequences for both wildlife and human populations. By providing this context, you are setting the stage for the rest of your research paper and helping the reader understand the importance of your study.

Presenting Your Thesis Statement

The thesis statement should directly address your research question and provide a preview of the main arguments or findings discussed in your paper. Make sure your thesis statement is clear, concise, and well-supported by the evidence you will present in your research paper. By presenting a strong and focused thesis statement, you are providing the reader with the information they could anticipate in your research paper. This will help them understand the purpose and scope of your study and will make them more inclined to continue reading.

Writing Techniques for an Effective Introduction

When crafting an introduction, it is crucial to pay attention to the finer details that can elevate your writing to the next level. By utilizing specific writing techniques, you can captivate your readers and draw them into your research journey.

Using Clear and Concise Language

One of the most important writing techniques to employ in your introduction is the use of clear and concise language. By choosing your words carefully, you can effectively convey your ideas to the reader. It is essential to avoid using jargon or complex terminology that may confuse or alienate your audience. Instead, focus on communicating your research in a straightforward manner to ensure that your introduction is accessible to both experts in your field and those who may be new to the topic. This approach allows you to engage a broader audience and make your research more inclusive.

Establishing the Relevance of Your Research

One way to establish the relevance of your research is by highlighting how it fills a gap in the existing literature. Explain how your study addresses a significant research question that has not been adequately explored. By doing this, you demonstrate that your research is not only unique but also contributes to the broader knowledge in your field. Furthermore, it is important to emphasize the potential impact of your research. Whether it is advancing scientific understanding, informing policy decisions, or improving practical applications, make it clear to the reader how your study can make a difference.

By employing these two writing techniques in your introduction, you can effectively engage your readers. Take your time to craft an introduction that is both informative and captivating, leaving your readers eager to delve deeper into your research.

Revising and Polishing Your Introduction

Once you have written your introduction, it is crucial to revise and polish it to ensure that it effectively sets the stage for your research paper.

Self-Editing Techniques

Review your introduction for clarity, coherence, and logical flow. Ensure each paragraph introduces a new idea or argument with smooth transitions.

Check for grammatical errors, spelling mistakes, and awkward sentence structures.

Ensure that your introduction aligns with the overall tone and style of your research paper.

Seeking Feedback for Improvement

Consider seeking feedback from peers, colleagues, or your instructor. They can provide valuable insights and suggestions for improving your introduction. Be open to constructive criticism and use it to refine your introduction and make it more compelling for the reader.

Writing an introduction for a research paper requires careful thought and planning. By understanding the purpose of the introduction, preparing adequately, structuring effectively, and employing writing techniques, you can create an engaging and informative introduction for your research. Remember to revise and polish your introduction to ensure that it accurately represents the main ideas and arguments in your research paper. With a well-crafted introduction, you will capture the reader's attention and keep them inclined to your paper.

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• If you are writing in a new discipline, you should always make sure to ask about conventions and expectations for introductions, just as you would for any other aspect of the essay. For example, while it may be acceptable to write a two-paragraph (or longer) introduction for your papers in some courses, instructors in other disciplines, such as those in some Government courses, may expect a shorter introduction that includes a preview of the argument that will follow.  
• In some disciplines (Government, Economics, and others), it’s common to offer an overview in the introduction of what points you will make in your essay. In other disciplines, you will not be expected to provide this overview in your introduction.  
• Avoid writing a very general opening sentence. While it may be true that “Since the dawn of time, people have been telling love stories,” it won’t help you explain what’s interesting about your topic.  
• Avoid writing a “funnel” introduction in which you begin with a very broad statement about a topic and move to a narrow statement about that topic. Broad generalizations about a topic will not add to your readers’ understanding of your specific essay topic.  
• Avoid beginning with a dictionary definition of a term or concept you will be writing about. If the concept is complicated or unfamiliar to your readers, you will need to define it in detail later in your essay. If it’s not complicated, you can assume your readers already know the definition.  
• Avoid offering too much detail in your introduction that a reader could better understand later in the paper.
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• Dissertation

How to Write a Thesis or Dissertation Introduction

Published on September 7, 2022 by Tegan George and Shona McCombes. Revised on November 21, 2023.

The introduction is the first section of your thesis or dissertation , appearing right after the table of contents . Your introduction draws your reader in, setting the stage for your research with a clear focus, purpose, and direction on a relevant topic .

Your introduction should include:

• Your topic, in context: what does your reader need to know to understand your thesis dissertation?
• Your focus and scope: what specific aspect of the topic will you address?
• The relevance of your research: how does your work fit into existing studies on your topic?
• Your questions and objectives: what does your research aim to find out, and how?
• An overview of your structure: what does each section contribute to the overall aim?

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Table of contents

How to start your introduction, topic and context, focus and scope, relevance and importance, questions and objectives, overview of the structure, thesis introduction example, introduction checklist, other interesting articles, frequently asked questions about introductions.

Although your introduction kicks off your dissertation, it doesn’t have to be the first thing you write — in fact, it’s often one of the very last parts to be completed (just before your abstract ).

It’s a good idea to write a rough draft of your introduction as you begin your research, to help guide you. If you wrote a research proposal , consider using this as a template, as it contains many of the same elements. However, be sure to revise your introduction throughout the writing process, making sure it matches the content of your ensuing sections.

Prevent plagiarism. Run a free check.

Begin by introducing your dissertation topic and giving any necessary background information. It’s important to contextualize your research and generate interest. Aim to show why your topic is timely or important. You may want to mention a relevant news item, academic debate, or practical problem.

After a brief introduction to your general area of interest, narrow your focus and define the scope of your research.

You can narrow this down in many ways, such as by:

• Geographical area
• Time period
• Demographics or communities
• Themes or aspects of the topic

It’s essential to share your motivation for doing this research, as well as how it relates to existing work on your topic. Further, you should also mention what new insights you expect it will contribute.

Start by giving a brief overview of the current state of research. You should definitely cite the most relevant literature, but remember that you will conduct a more in-depth survey of relevant sources in the literature review section, so there’s no need to go too in-depth in the introduction.

Depending on your field, the importance of your research might focus on its practical application (e.g., in policy or management) or on advancing scholarly understanding of the topic (e.g., by developing theories or adding new empirical data). In many cases, it will do both.

Ultimately, your introduction should explain how your thesis or dissertation:

• Helps solve a practical or theoretical problem
• Addresses a gap in the literature
• Builds on existing research
• Proposes a new understanding of your topic

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Perhaps the most important part of your introduction is your questions and objectives, as it sets up the expectations for the rest of your thesis or dissertation. How you formulate your research questions and research objectives will depend on your discipline, topic, and focus, but you should always clearly state the central aim of your research.

If your research aims to test hypotheses , you can formulate them here. Your introduction is also a good place for a conceptual framework that suggests relationships between variables .

• Conduct surveys to collect data on students’ levels of knowledge, understanding, and positive/negative perceptions of government policy.
• Determine whether attitudes to climate policy are associated with variables such as age, gender, region, and social class.
• Conduct interviews to gain qualitative insights into students’ perspectives and actions in relation to climate policy.

To help guide your reader, end your introduction with an outline  of the structure of the thesis or dissertation to follow. Share a brief summary of each chapter, clearly showing how each contributes to your central aims. However, be careful to keep this overview concise: 1-2 sentences should be enough.

I. Introduction

Human language consists of a set of vowels and consonants which are combined to form words. During the speech production process, thoughts are converted into spoken utterances to convey a message. The appropriate words and their meanings are selected in the mental lexicon (Dell & Burger, 1997). This pre-verbal message is then grammatically coded, during which a syntactic representation of the utterance is built.

Speech, language, and voice disorders affect the vocal cords, nerves, muscles, and brain structures, which result in a distorted language reception or speech production (Sataloff & Hawkshaw, 2014). The symptoms vary from adding superfluous words and taking pauses to hoarseness of the voice, depending on the type of disorder (Dodd, 2005). However, distortions of the speech may also occur as a result of a disease that seems unrelated to speech, such as multiple sclerosis or chronic obstructive pulmonary disease.

This study aims to determine which acoustic parameters are suitable for the automatic detection of exacerbations in patients suffering from chronic obstructive pulmonary disease (COPD) by investigating which aspects of speech differ between COPD patients and healthy speakers and which aspects differ between COPD patients in exacerbation and stable COPD patients.

Checklist: Introduction

I have introduced my research topic in an engaging way.

I have provided necessary context to help the reader understand my topic.

I have clearly specified the focus of my research.

I have shown the relevance and importance of the dissertation topic .

I have clearly stated the problem or question that my research addresses.

I have outlined the specific objectives of the research .

I have provided an overview of the dissertation’s structure .

You've written a strong introduction for your thesis or dissertation. Use the other checklists to continue improving your dissertation.

If you want to know more about AI for academic writing, AI tools, or research bias, make sure to check out some of our other articles with explanations and examples or go directly to our tools!

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The introduction of a research paper includes several key elements:

• A hook to catch the reader’s interest
• Relevant background on the topic
• Details of your research problem

and your problem statement

• A thesis statement or research question
• Sometimes an overview of the paper

Don’t feel that you have to write the introduction first. The introduction is often one of the last parts of the research paper you’ll write, along with the conclusion.

This is because it can be easier to introduce your paper once you’ve already written the body ; you may not have the clearest idea of your arguments until you’ve written them, and things can change during the writing process .

Research objectives describe what you intend your research project to accomplish.

They summarize the approach and purpose of the project and help to focus your research.

Your objectives should appear in the introduction of your research paper , at the end of your problem statement .

Scope of research is determined at the beginning of your research process , prior to the data collection stage. Sometimes called “scope of study,” your scope delineates what will and will not be covered in your project. It helps you focus your work and your time, ensuring that you’ll be able to achieve your goals and outcomes.

Defining a scope can be very useful in any research project, from a research proposal to a thesis or dissertation . A scope is needed for all types of research: quantitative , qualitative , and mixed methods .

To define your scope of research, consider the following:

• Budget constraints or any specifics of grant funding
• Your proposed timeline and duration
• Specifics about your population of study, your proposed sample size , and the research methodology you’ll pursue
• Any inclusion and exclusion criteria
• Any anticipated control , extraneous , or confounding variables that could bias your research if not accounted for properly.

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How to Write an Introduction for a Research Paper

How to write an introduction for a research paper? Eventually (and with practice) all writers will develop their own strategy for writing the perfect introduction for a research paper. Once you are comfortable with writing, you will probably find your own, but coming up with a good strategy can be tough for beginning writers.

The Purpose of an Introduction

Your opening paragraphs, phrases for introducing thesis statements, research paper introduction examples, using the introduction to map out your research paper.

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• First write your thesis.Your thesis should state the main idea in specific terms.
• After you have a working thesis, tackle the body of your paper before you write the rest of the introduction. Each paragraph in the body should explore one specific topic that proves, or summarizes your thesis. Writing is a thinking process. Once you have worked your way through that process by writing the body of the paper, you will have an intimate understanding of how you are supporting your thesis. After you have written the body paragraphs, go back and rewrite your thesis to make it more specific and to connect it to the topics you addressed in the body paragraph.
• Revise your introduction several times, saving each revision. Be sure your introduction previews the topics you are presenting in your paper. One way of doing this is to use keywords from the topic sentences in each paragraph to introduce, or preview, the topics in your introduction.This “preview” will give your reader a context for understanding how you will make your case.
• Experiment by taking different approaches to your thesis with every revision you make. Play with the language in the introduction. Strike a new tone. Go back and compare versions. Then pick the one that works most effectively with the body of your research paper.
• Do not try to pack everything you want to say into your introduction. Just as your introduction should not be too short, it should also not be too long. Your introduction should be about the same length as any other paragraph in your research paper. Let the content—what you have to say—dictate the length.

The first page of your research paper should draw the reader into the text. It is the paper’s most important page and, alas, often the worst written. There are two culprits here and effective ways to cope with both of them.

First, the writer is usually straining too hard to say something terribly BIG and IMPORTANT about the thesis topic. The goal is worthy, but the aim is unrealistically high. The result is often a muddle of vague platitudes rather than a crisp, compelling introduction to the thesis. Want a familiar example? Listen to most graduation speakers. Their goal couldn’t be loftier: to say what education means and to tell an entire football stadium how to live the rest of their lives. The results are usually an avalanche of clichés and sodden prose.

The second culprit is bad timing. The opening and concluding paragraphs are usually written late in the game, after the rest of the thesis is finished and polished. There’s nothing wrong with writing these sections last. It’s usually the right approach since you need to know exactly what you are saying in the substantive middle sections of the thesis before you can introduce them effectively or draw together your findings. But having waited to write the opening and closing sections, you need to review and edit them several times to catch up. Otherwise, you’ll putting the most jagged prose in the most tender spots. Edit and polish your opening paragraphs with extra care. They should draw readers into the paper.

After you’ve done some extra polishing, I suggest a simple test for the introductory section. As an experiment, chop off the first few paragraphs. Let the paper begin on, say, paragraph 2 or even page 2. If you don’t lose much, or actually gain in clarity and pace, then you’ve got a problem.

There are two solutions. One is to start at this new spot, further into the text. After all, that’s where you finally gain traction on your subject. That works best in some cases, and we occasionally suggest it. The alternative, of course, is to write a new opening that doesn’t flop around, saying nothing.

What makes a good opening? Actually, they come in several flavors. One is an intriguing story about your topic. Another is a brief, compelling quote. When you run across them during your reading, set them aside for later use. Don’t be deterred from using them because they “don’t seem academic enough.” They’re fine as long as the rest of the paper doesn’t sound like you did your research in People magazine. The third, and most common, way to begin is by stating your main questions, followed by a brief comment about why they matter.

Whichever opening you choose, it should engage your readers and coax them to continue. Having done that, you should give them a general overview of the project—the main issues you will cover, the material you will use, and your thesis statement (that is, your basic approach to the topic). Finally, at the end of the introductory section, give your readers a brief road map, showing how the paper will unfold. How you do that depends on your topic but here are some general suggestions for phrase choice that may help:

• This analysis will provide …
• This paper analyzes the relationship between …
• This paper presents an analysis of …
• This paper will argue that …
• This topic supports the argument that…
• Research supports the opinion that …
• This paper supports the opinion that …
• An interpretation of the facts indicates …
• The results of this experiment show …
• The results of this research show …

Comparisons/Contrasts

• A comparison will show that …
• By contrasting the results,we see that …
• This paper examines the advantages and disadvantages of …

Definitions/Classifications

• This paper will provide a guide for categorizing the following:…
• This paper provides a definition of …
• This paper explores the meaning of …
• This paper will discuss the implications of …
• A discussion of this topic reveals …
• The following discussion will focus on …

Description

• This report describes…
• This report will illustrate…
• This paper provides an illustration of …

Process/Experimentation

• This paper will identify the reasons behind…
• The results of the experiment show …
• The process revealed that …
• This paper theorizes…
• This paper presents the theory that …
• In theory, this indicates that …

Quotes, anecdotes, questions, examples, and broad statements—all of them can used successfully to write an introduction for a research paper. It’s instructive to see them in action, in the hands of skilled academic writers.

Let’s begin with David M. Kennedy’s superb history, Freedom from Fear: The American People in Depression and War, 1929–1945 . Kennedy begins each chapter with a quote, followed by his text. The quote above chapter 1 shows President Hoover speaking in 1928 about America’s golden future. The text below it begins with the stock market collapse of 1929. It is a riveting account of just how wrong Hoover was. The text about the Depression is stronger because it contrasts so starkly with the optimistic quotation.

“We in America today are nearer the final triumph over poverty than ever before in the history of any land.”—Herbert Hoover, August 11, 1928 Like an earthquake, the stock market crash of October 1929 cracked startlingly across the United States, the herald of a crisis that was to shake the American way of life to its foundations. The events of the ensuing decade opened a fissure across the landscape of American history no less gaping than that opened by the volley on Lexington Common in April 1775 or by the bombardment of Sumter on another April four score and six years later. The ratcheting ticker machines in the autumn of 1929 did not merely record avalanching stock prices. In time they came also to symbolize the end of an era. (David M. Kennedy, Freedom from Fear: The American People in Depression and War, 1929–1945 . New York: Oxford University Press, 1999, p. 10)

Kennedy has exciting, wrenching material to work with. John Mueller faces the exact opposite problem. In Retreat from Doomsday: The Obsolescence of Major War , he is trying to explain why Great Powers have suddenly stopped fighting each other. For centuries they made war on each other with devastating regularity, killing millions in the process. But now, Mueller thinks, they have not just paused; they have stopped permanently. He is literally trying to explain why “nothing is happening now.” That may be an exciting topic intellectually, it may have great practical significance, but “nothing happened” is not a very promising subject for an exciting opening paragraph. Mueller manages to make it exciting and, at the same time, shows why it matters so much. Here’s his opening, aptly entitled “History’s Greatest Nonevent”:

On May 15, 1984, the major countries of the developed world had managed to remain at peace with each other for the longest continuous stretch of time since the days of the Roman Empire. If a significant battle in a war had been fought on that day, the press would have bristled with it. As usual, however, a landmark crossing in the history of peace caused no stir: the most prominent story in the New York Times that day concerned the saga of a manicurist, a machinist, and a cleaning woman who had just won a big Lotto contest. This book seeks to develop an explanation for what is probably the greatest nonevent in human history. (John Mueller, Retreat from Doomsday: The Obsolescence of Major War . New York: Basic Books, 1989, p. 3)

In the space of a few sentences, Mueller sets up his puzzle and reveals its profound human significance. At the same time, he shows just how easy it is to miss this milestone in the buzz of daily events. Notice how concretely he does that. He doesn’t just say that the New York Times ignored this record setting peace. He offers telling details about what they covered instead: “a manicurist, a machinist, and a cleaning woman who had just won a big Lotto contest.” Likewise, David Kennedy immediately entangles us in concrete events: the stunning stock market crash of 1929. These are powerful openings that capture readers’ interests, establish puzzles, and launch narratives.

Sociologist James Coleman begins in a completely different way, by posing the basic questions he will study. His ambitious book, Foundations of Social Theory , develops a comprehensive theory of social life, so it is entirely appropriate for him to begin with some major questions. But he could just as easily have begun with a compelling story or anecdote. He includes many of them elsewhere in his book. His choice for the opening, though, is to state his major themes plainly and frame them as a paradox. Sociologists, he says, are interested in aggregate behavior—how people act in groups, organizations, or large numbers—yet they mostly examine individuals:

A central problem in social science is that of accounting for the function of some kind of social system. Yet in most social research, observations are not made on the system as a whole, but on some part of it. In fact, the natural unit of observation is the individual person…  This has led to a widening gap between theory and research… (James S. Coleman, Foundations of Social Theory . Cambridge, MA: Harvard University Press, 1990, pp. 1–2)

After expanding on this point, Coleman explains that he will not try to remedy the problem by looking solely at groups or aggregate-level data. That’s a false solution, he says, because aggregates don’t act; individuals do. So the real problem is to show the links between individual actions and aggregate outcomes, between the micro and the macro.

The major problem for explanations of system behavior based on actions and orientations at a level below that of the system [in this case, on individual-level actions] is that of moving from the lower level to the system level. This has been called the micro-to-macro problem, and it is pervasive throughout the social sciences. (Coleman, Foundations of Social Theory , p. 6)

Explaining how to deal with this “micro-to-macro problem” is the central issue of Coleman’s book, and he announces it at the beginning.

Coleman’s theory-driven opening stands at the opposite end of the spectrum from engaging stories or anecdotes, which are designed to lure the reader into the narrative and ease the path to a more analytic treatment later in the text. Take, for example, the opening sentences of Robert L. Herbert’s sweeping study Impressionism: Art, Leisure, and Parisian Society : “When Henry Tuckerman came to Paris in 1867, one of the thousands of Americans attracted there by the huge international exposition, he was bowled over by the extraordinary changes since his previous visit twenty years before.” (Robert L. Herbert, Impressionism: Art, Leisure, and Parisian Society . New Haven, CT: Yale University Press, 1988, p. 1.) Herbert fills in the evocative details to set the stage for his analysis of the emerging Impressionist art movement and its connection to Parisian society and leisure in this period.

David Bromwich writes about Wordsworth, a poet so familiar to students of English literature that it is hard to see him afresh, before his great achievements, when he was just a young outsider starting to write. To draw us into Wordsworth’s early work, Bromwich wants us to set aside our entrenched images of the famous mature poet and see him as he was in the 1790s, as a beginning writer on the margins of society. He accomplishes this ambitious task in the opening sentences of Disowned by Memory: Wordsworth’s Poetry of the 1790s :

Wordsworth turned to poetry after the revolution to remind himself that he was still a human being. It was a curious solution, to a difficulty many would not have felt. The whole interest of his predicament is that he did feel it. Yet Wordsworth is now so established an eminence—his name so firmly fixed with readers as a moralist of self-trust emanating from complete self-security—that it may seem perverse to imagine him as a criminal seeking expiation. Still, that is a picture we get from The Borderers and, at a longer distance, from “Tintern Abbey.” (David Bromwich, Disowned by Memory: Wordsworth’s Poetry of the 1790s . Chicago: University of Chicago Press, 1998, p. 1)

That’s a wonderful opening! Look at how much Bromwich accomplishes in just a few words. He not only prepares the way for analyzing Wordsworth’s early poetry; he juxtaposes the anguished young man who wrote it to the self-confident, distinguished figure he became—the eminent man we can’t help remembering as we read his early poetry.

Let us highlight a couple of other points in this passage because they illustrate some intelligent writing choices. First, look at the odd comma in this sentence: “It was a curious solution, to a difficulty many would not have felt.” Any standard grammar book would say that comma is wrong and should be omitted. Why did Bromwich insert it? Because he’s a fine writer, thinking of his sentence rhythm and the point he wants to make. The comma does exactly what it should. It makes us pause, breaking the sentence into two parts, each with an interesting point. One is that Wordsworth felt a difficulty others would not have; the other is that he solved it in a distinctive way. It would be easy for readers to glide over this double message, so Bromwich has inserted a speed bump to slow us down. Most of the time, you should follow grammatical rules, like those about commas, but you should bend them when it serves a good purpose. That’s what the writer does here.

The second small point is the phrase “after the revolution” in the first sentence: “Wordsworth turned to poetry after the revolution to remind himself that he was still a human being.” Why doesn’t Bromwich say “after the French Revolution”? Because he has judged his book’s audience. He is writing for specialists who already know which revolution is reverberating through English life in the 1790s. It is the French Revolution, not the earlier loss of the American colonies. If Bromwich were writing for a much broader audience—say, the New York Times Book Review—he would probably insert the extra word to avoid confusion.

The message “Know your audience” applies to all writers. Don’t talk down to them by assuming they can’t get dressed in the morning. Don’t strut around showing off your book learnin’ by tossing in arcane facts and esoteric language for its own sake. Neither will win over readers.

Bromwich, Herbert, and Coleman open their works in different ways, but their choices work well for their different texts. Your task is to decide what kind of opening will work best for yours. Don’t let that happen by default, by grabbing the first idea you happen upon. Consider a couple of different ways of opening your thesis and then choose the one you prefer. Give yourself some options, think them over, then make an informed choice.

Whether you begin with a story, puzzle, or broad statement, the next part of the introduction should pose your main questions and establish your argument. This is your thesis statement—your viewpoint along with the supporting reasons and evidence. It should be articulated plainly so readers understand full well what your paper is about and what it will argue.

After that, give your readers a road map of what’s to come. That’s normally done at the end of the introductory section (or, in a book, at the end of the introductory chapter). Here’s John J. Mearsheimer presenting such a road map in The Tragedy of Great Power Politics . He not only tells us the order of upcoming chapters, he explains why he’s chosen that order and which chapters are most important:

The Plan of the Book The rest of the chapters in this book are concerned mainly with answering the six big questions about power which I identified earlier. Chapter 2, which is probably the most important chapter in the book, lays out my theory of why states compete for power and why they pursue hegemony. In Chapters 3 and 4, I define power and explain how to measure it. I do this in order to lay the groundwork for testing my theory… (John J. Mearsheimer, The Tragedy of Great Power Politics . New York: W. W. Norton, 2001, p. 27)

As this excerpt makes clear, Mearsheimer has already laid out his “six big questions” in the introduction. Now he’s showing us the path ahead, the path to answering those questions.

At the end of the introduction, give your readers a road map of what’s to come. Tell them what the upcoming sections will be and why they are arranged in this particular order.

After having written your introduction it’s time to move to the biggest part: body of a research paper.

Back to How To Write A Research Paper .

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Organizing Your Social Sciences Research Paper

• 4. The Introduction
• Purpose of Guide
• Design Flaws to Avoid
• Independent and Dependent Variables
• Glossary of Research Terms
• Reading Research Effectively
• Narrowing a Topic Idea
• Broadening a Topic Idea
• Extending the Timeliness of a Topic Idea
• Academic Writing Style
• Applying Critical Thinking
• Choosing a Title
• Making an Outline
• Paragraph Development
• Research Process Video Series
• Executive Summary
• The C.A.R.S. Model
• Background Information
• The Research Problem/Question
• Theoretical Framework
• Citation Tracking
• Content Alert Services
• Evaluating Sources
• Primary Sources
• Secondary Sources
• Tiertiary Sources
• Scholarly vs. Popular Publications
• Qualitative Methods
• Quantitative Methods
• Insiderness
• Using Non-Textual Elements
• Limitations of the Study
• Common Grammar Mistakes
• Writing Concisely
• Avoiding Plagiarism
• Footnotes or Endnotes?
• Further Readings
• Generative AI and Writing
• USC Libraries Tutorials and Other Guides
• Bibliography

The introduction leads the reader from a general subject area to a particular topic of inquiry. It establishes the scope, context, and significance of the research being conducted by summarizing current understanding and background information about the topic, stating the purpose of the work in the form of the research problem supported by a hypothesis or a set of questions, explaining briefly the methodological approach used to examine the research problem, highlighting the potential outcomes your study can reveal, and outlining the remaining structure and organization of the paper.

Key Elements of the Research Proposal. Prepared under the direction of the Superintendent and by the 2010 Curriculum Design and Writing Team. Baltimore County Public Schools.

Importance of a Good Introduction

Think of the introduction as a mental road map that must answer for the reader these four questions:

• What was I studying?
• Why was this topic important to investigate?
• What did we know about this topic before I did this study?
• How will this study advance new knowledge or new ways of understanding?

According to Reyes, there are three overarching goals of a good introduction: 1) ensure that you summarize prior studies about the topic in a manner that lays a foundation for understanding the research problem; 2) explain how your study specifically addresses gaps in the literature, insufficient consideration of the topic, or other deficiency in the literature; and, 3) note the broader theoretical, empirical, and/or policy contributions and implications of your research.

A well-written introduction is important because, quite simply, you never get a second chance to make a good first impression. The opening paragraphs of your paper will provide your readers with their initial impressions about the logic of your argument, your writing style, the overall quality of your research, and, ultimately, the validity of your findings and conclusions. A vague, disorganized, or error-filled introduction will create a negative impression, whereas, a concise, engaging, and well-written introduction will lead your readers to think highly of your analytical skills, your writing style, and your research approach. All introductions should conclude with a brief paragraph that describes the organization of the rest of the paper.

Hirano, Eliana. “Research Article Introductions in English for Specific Purposes: A Comparison between Brazilian, Portuguese, and English.” English for Specific Purposes 28 (October 2009): 240-250; Samraj, B. “Introductions in Research Articles: Variations Across Disciplines.” English for Specific Purposes 21 (2002): 1–17; Introductions. The Writing Center. University of North Carolina; “Writing Introductions.” In Good Essay Writing: A Social Sciences Guide. Peter Redman. 4th edition. (London: Sage, 2011), pp. 63-70; Reyes, Victoria. Demystifying the Journal Article. Inside Higher Education.

Structure and Writing Style

I.  Structure and Approach

The introduction is the broad beginning of the paper that answers three important questions for the reader:

• What is this?
• Why should I read it?
• What do you want me to think about / consider doing / react to?

Think of the structure of the introduction as an inverted triangle of information that lays a foundation for understanding the research problem. Organize the information so as to present the more general aspects of the topic early in the introduction, then narrow your analysis to more specific topical information that provides context, finally arriving at your research problem and the rationale for studying it [often written as a series of key questions to be addressed or framed as a hypothesis or set of assumptions to be tested] and, whenever possible, a description of the potential outcomes your study can reveal.

These are general phases associated with writing an introduction: 1.  Establish an area to research by:

• Highlighting the importance of the topic, and/or
• Making general statements about the topic, and/or
• Presenting an overview on current research on the subject.

2.  Identify a research niche by:

• Opposing an existing assumption, and/or
• Revealing a gap in existing research, and/or
• Formulating a research question or problem, and/or
• Continuing a disciplinary tradition.

3.  Place your research within the research niche by:

• Stating the intent of your study,
• Outlining the key characteristics of your study,
• Describing important results, and
• Giving a brief overview of the structure of the paper.

NOTE:   It is often useful to review the introduction late in the writing process. This is appropriate because outcomes are unknown until you've completed the study. After you complete writing the body of the paper, go back and review introductory descriptions of the structure of the paper, the method of data gathering, the reporting and analysis of results, and the conclusion. Reviewing and, if necessary, rewriting the introduction ensures that it correctly matches the overall structure of your final paper.

II.  Delimitations of the Study

Delimitations refer to those characteristics that limit the scope and define the conceptual boundaries of your research . This is determined by the conscious exclusionary and inclusionary decisions you make about how to investigate the research problem. In other words, not only should you tell the reader what it is you are studying and why, but you must also acknowledge why you rejected alternative approaches that could have been used to examine the topic.

Obviously, the first limiting step was the choice of research problem itself. However, implicit are other, related problems that could have been chosen but were rejected. These should be noted in the conclusion of your introduction. For example, a delimitating statement could read, "Although many factors can be understood to impact the likelihood young people will vote, this study will focus on socioeconomic factors related to the need to work full-time while in school." The point is not to document every possible delimiting factor, but to highlight why previously researched issues related to the topic were not addressed.

Examples of delimitating choices would be:

• The key aims and objectives of your study,
• The research questions that you address,
• The variables of interest [i.e., the various factors and features of the phenomenon being studied],
• The method(s) of investigation,
• The time period your study covers, and
• Any relevant alternative theoretical frameworks that could have been adopted.

Review each of these decisions. Not only do you clearly establish what you intend to accomplish in your research, but you should also include a declaration of what the study does not intend to cover. In the latter case, your exclusionary decisions should be based upon criteria understood as, "not interesting"; "not directly relevant"; “too problematic because..."; "not feasible," and the like. Make this reasoning explicit!

NOTE:   Delimitations refer to the initial choices made about the broader, overall design of your study and should not be confused with documenting the limitations of your study discovered after the research has been completed.

ANOTHER NOTE: Do not view delimitating statements as admitting to an inherent failing or shortcoming in your research. They are an accepted element of academic writing intended to keep the reader focused on the research problem by explicitly defining the conceptual boundaries and scope of your study. It addresses any critical questions in the reader's mind of, "Why the hell didn't the author examine this?"

III.  The Narrative Flow

Issues to keep in mind that will help the narrative flow in your introduction :

• Your introduction should clearly identify the subject area of interest . A simple strategy to follow is to use key words from your title in the first few sentences of the introduction. This will help focus the introduction on the topic at the appropriate level and ensures that you get to the subject matter quickly without losing focus, or discussing information that is too general.
• Establish context by providing a brief and balanced review of the pertinent published literature that is available on the subject. The key is to summarize for the reader what is known about the specific research problem before you did your analysis. This part of your introduction should not represent a comprehensive literature review--that comes next. It consists of a general review of the important, foundational research literature [with citations] that establishes a foundation for understanding key elements of the research problem. See the drop-down menu under this tab for " Background Information " regarding types of contexts.
• Clearly state the hypothesis that you investigated . When you are first learning to write in this format it is okay, and actually preferable, to use a past statement like, "The purpose of this study was to...." or "We investigated three possible mechanisms to explain the...."
• Why did you choose this kind of research study or design? Provide a clear statement of the rationale for your approach to the problem studied. This will usually follow your statement of purpose in the last paragraph of the introduction.

IV.  Engaging the Reader

A research problem in the social sciences can come across as dry and uninteresting to anyone unfamiliar with the topic . Therefore, one of the goals of your introduction is to make readers want to read your paper. Here are several strategies you can use to grab the reader's attention:

• Open with a compelling story . Almost all research problems in the social sciences, no matter how obscure or esoteric , are really about the lives of people. Telling a story that humanizes an issue can help illuminate the significance of the problem and help the reader empathize with those affected by the condition being studied.
• Include a strong quotation or a vivid, perhaps unexpected, anecdote . During your review of the literature, make note of any quotes or anecdotes that grab your attention because they can used in your introduction to highlight the research problem in a captivating way.
• Pose a provocative or thought-provoking question . Your research problem should be framed by a set of questions to be addressed or hypotheses to be tested. However, a provocative question can be presented in the beginning of your introduction that challenges an existing assumption or compels the reader to consider an alternative viewpoint that helps establish the significance of your study. 
• Describe a puzzling scenario or incongruity . This involves highlighting an interesting quandary concerning the research problem or describing contradictory findings from prior studies about a topic. Posing what is essentially an unresolved intellectual riddle about the problem can engage the reader's interest in the study.
• Cite a stirring example or case study that illustrates why the research problem is important . Draw upon the findings of others to demonstrate the significance of the problem and to describe how your study builds upon or offers alternatives ways of investigating this prior research.

NOTE:   It is important that you choose only one of the suggested strategies for engaging your readers. This avoids giving an impression that your paper is more flash than substance and does not distract from the substance of your study.

Freedman, Leora  and Jerry Plotnick. Introductions and Conclusions. University College Writing Centre. University of Toronto; Introduction. The Structure, Format, Content, and Style of a Journal-Style Scientific Paper. Department of Biology. Bates College; Introductions. The Writing Center. University of North Carolina; Introductions. The Writer’s Handbook. Writing Center. University of Wisconsin, Madison; Introductions, Body Paragraphs, and Conclusions for an Argument Paper. The Writing Lab and The OWL. Purdue University; “Writing Introductions.” In Good Essay Writing: A Social Sciences Guide . Peter Redman. 4th edition. (London: Sage, 2011), pp. 63-70; Resources for Writers: Introduction Strategies. Program in Writing and Humanistic Studies. Massachusetts Institute of Technology; Sharpling, Gerald. Writing an Introduction. Centre for Applied Linguistics, University of Warwick; Samraj, B. “Introductions in Research Articles: Variations Across Disciplines.” English for Specific Purposes 21 (2002): 1–17; Swales, John and Christine B. Feak. Academic Writing for Graduate Students: Essential Skills and Tasks . 2nd edition. Ann Arbor, MI: University of Michigan Press, 2004 ; Writing Your Introduction. Department of English Writing Guide. George Mason University.

Writing Tip

Avoid the "Dictionary" Introduction

Giving the dictionary definition of words related to the research problem may appear appropriate because it is important to define specific terminology that readers may be unfamiliar with. However, anyone can look a word up in the dictionary and a general dictionary is not a particularly authoritative source because it doesn't take into account the context of your topic and doesn't offer particularly detailed information. Also, placed in the context of a particular discipline, a term or concept may have a different meaning than what is found in a general dictionary. If you feel that you must seek out an authoritative definition, use a subject specific dictionary or encyclopedia [e.g., if you are a sociology student, search for dictionaries of sociology]. A good database for obtaining definitive definitions of concepts or terms is Credo Reference .

Saba, Robert. The College Research Paper. Florida International University; Introductions. The Writing Center. University of North Carolina.

Another Writing Tip

When Do I Begin?

A common question asked at the start of any paper is, "Where should I begin?" An equally important question to ask yourself is, "When do I begin?" Research problems in the social sciences rarely rest in isolation from history. Therefore, it is important to lay a foundation for understanding the historical context underpinning the research problem. However, this information should be brief and succinct and begin at a point in time that illustrates the study's overall importance. For example, a study that investigates coffee cultivation and export in West Africa as a key stimulus for local economic growth needs to describe the beginning of exporting coffee in the region and establishing why economic growth is important. You do not need to give a long historical explanation about coffee exports in Africa. If a research problem requires a substantial exploration of the historical context, do this in the literature review section. In your introduction, make note of this as part of the "roadmap" [see below] that you use to describe the organization of your paper.

Introductions. The Writing Center. University of North Carolina; “Writing Introductions.” In Good Essay Writing: A Social Sciences Guide . Peter Redman. 4th edition. (London: Sage, 2011), pp. 63-70.

Yet Another Writing Tip

Always End with a Roadmap

The final paragraph or sentences of your introduction should forecast your main arguments and conclusions and provide a brief description of the rest of the paper [the "roadmap"] that let's the reader know where you are going and what to expect. A roadmap is important because it helps the reader place the research problem within the context of their own perspectives about the topic. In addition, concluding your introduction with an explicit roadmap tells the reader that you have a clear understanding of the structural purpose of your paper. In this way, the roadmap acts as a type of promise to yourself and to your readers that you will follow a consistent and coherent approach to addressing the topic of inquiry. Refer to it often to help keep your writing focused and organized.

Cassuto, Leonard. “On the Dissertation: How to Write the Introduction.” The Chronicle of Higher Education , May 28, 2018; Radich, Michael. A Student's Guide to Writing in East Asian Studies . (Cambridge, MA: Harvard University Writing n. d.), pp. 35-37.

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How to Write a Research Introduction

Last Updated: December 6, 2023 Fact Checked

This article was co-authored by Megan Morgan, PhD . Megan Morgan is a Graduate Program Academic Advisor in the School of Public & International Affairs at the University of Georgia. She earned her PhD in English from the University of Georgia in 2015. There are 7 references cited in this article, which can be found at the bottom of the page. This article has been fact-checked, ensuring the accuracy of any cited facts and confirming the authority of its sources. This article has been viewed 2,654,699 times.

The introduction to a research paper can be the most challenging part of the paper to write. The length of the introduction will vary depending on the type of research paper you are writing. An introduction should announce your topic, provide context and a rationale for your work, before stating your research questions and hypothesis. Well-written introductions set the tone for the paper, catch the reader's interest, and communicate the hypothesis or thesis statement.

Introducing the Topic of the Paper

• In scientific papers this is sometimes known as an "inverted triangle", where you start with the broadest material at the start, before zooming in on the specifics. [2] X Research source
• The sentence "Throughout the 20th century, our views of life on other planets have drastically changed" introduces a topic, but does so in broad terms.
• It provides the reader with an indication of the content of the essay and encourages them to read on.

• For example, if you were writing a paper about the behaviour of mice when exposed to a particular substance, you would include the word "mice", and the scientific name of the relevant compound in the first sentences.
• If you were writing a history paper about the impact of the First World War on gender relations in Britain, you should mention those key words in your first few lines.

• This is especially important if you are attempting to develop a new conceptualization that uses language and terminology your readers may be unfamiliar with.

• If you use an anecdote ensure that is short and highly relevant for your research. It has to function in the same way as an alternative opening, namely to announce the topic of your research paper to your reader.
• For example, if you were writing a sociology paper about re-offending rates among young offenders, you could include a brief story of one person whose story reflects and introduces your topic.
• This kind of approach is generally not appropriate for the introduction to a natural or physical sciences research paper where the writing conventions are different.

Establishing the Context for Your Paper

• It is important to be concise in the introduction, so provide an overview on recent developments in the primary research rather than a lengthy discussion.
• You can follow the "inverted triangle" principle to focus in from the broader themes to those to which you are making a direct contribution with your paper.
• A strong literature review presents important background information to your own research and indicates the importance of the field.

• By making clear reference to existing work you can demonstrate explicitly the specific contribution you are making to move the field forward.
• You can identify a gap in the existing scholarship and explain how you are addressing it and moving understanding forward.

• For example, if you are writing a scientific paper you could stress the merits of the experimental approach or models you have used.
• Stress what is novel in your research and the significance of your new approach, but don't give too much detail in the introduction.
• A stated rationale could be something like: "the study evaluates the previously unknown anti-inflammatory effects of a topical compound in order to evaluate its potential clinical uses".

Specifying Your Research Questions and Hypothesis

• The research question or questions generally come towards the end of the introduction, and should be concise and closely focused.
• The research question might recall some of the key words established in the first few sentences and the title of your paper.
• An example of a research question could be "what were the consequences of the North American Free Trade Agreement on the Mexican export economy?"
• This could be honed further to be specific by referring to a particular element of the Free Trade Agreement and the impact on a particular industry in Mexico, such as clothing manufacture.
• A good research question should shape a problem into a testable hypothesis.

• If possible try to avoid using the word "hypothesis" and rather make this implicit in your writing. This can make your writing appear less formulaic.
• In a scientific paper, giving a clear one-sentence overview of your results and their relation to your hypothesis makes the information clear and accessible. [10] X Trustworthy Source PubMed Central Journal archive from the U.S. National Institutes of Health Go to source
• An example of a hypothesis could be "mice deprived of food for the duration of the study were expected to become more lethargic than those fed normally".

• This is not always necessary and you should pay attention to the writing conventions in your discipline.
• In a natural sciences paper, for example, there is a fairly rigid structure which you will be following.
• A humanities or social science paper will most likely present more opportunities to deviate in how you structure your paper.

Research Introduction Help

Community Q&A

• Use your research papers' outline to help you decide what information to include when writing an introduction. Thanks Helpful 0 Not Helpful 1
• Consider drafting your introduction after you have already completed the rest of your research paper. Writing introductions last can help ensure that you don't leave out any major points. Thanks Helpful 0 Not Helpful 0

• Avoid emotional or sensational introductions; these can create distrust in the reader. Thanks Helpful 50 Not Helpful 12
• Generally avoid using personal pronouns in your introduction, such as "I," "me," "we," "us," "my," "mine," or "our." Thanks Helpful 31 Not Helpful 7
• Don't overwhelm the reader with an over-abundance of information. Keep the introduction as concise as possible by saving specific details for the body of your paper. Thanks Helpful 24 Not Helpful 14

You Might Also Like

• ↑ https://library.sacredheart.edu/c.php?g=29803&p=185916
• ↑ https://www.aresearchguide.com/inverted-pyramid-structure-in-writing.html
• ↑ https://libguides.usc.edu/writingguide/introduction
• ↑ https://writing.wisc.edu/Handbook/PlanResearchPaper.html
• ↑ https://dept.writing.wisc.edu/wac/writing-an-introduction-for-a-scientific-paper/
• ↑ https://writing.wisc.edu/handbook/assignments/planresearchpaper/
• ↑ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3178846/

About This Article

To introduce your research paper, use the first 1-2 sentences to describe your general topic, such as “women in World War I.” Include and define keywords, such as “gender relations,” to show your reader where you’re going. Mention previous research into the topic with a phrase like, “Others have studied…”, then transition into what your contribution will be and why it’s necessary. Finally, state the questions that your paper will address and propose your “answer” to them as your thesis statement. For more information from our English Ph.D. co-author about how to craft a strong hypothesis and thesis, keep reading! Did this summary help you? Yes No

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How to Write an Introduction For a Research Paper

Learn how to write a strong and efficient research paper introduction by following the suitable structure and avoiding typical errors.

An introduction to any type of paper is sometimes misunderstood as the beginning; yet, an introduction is actually intended to present your chosen subject to the audience in a way that makes it more appealing and leaves your readers thirsty for more information. After the title and abstract, your audience will read the introduction, thus it’s critical to get off to a solid start.  

This article includes instructions on how to write an introduction for a research paper that engages the reader in your research. You can produce a strong opening for your research paper if you stick to the format and a few basic principles.

What is An Introduction To a Research Paper?

An introduction is the opening section of a research paper and the section that a reader is likely to read first, in which the objective and goals of the subsequent writing are stated. 

The introduction serves numerous purposes. It provides context for your research, explains your topic and objectives, and provides an outline of the work. A solid introduction will establish the tone for the remainder of your paper, enticing readers to continue reading through the methodology, findings, and discussion. 

Even though introductions are generally presented at the beginning of a document, we must distinguish an introduction from the beginning of your research. An introduction, as the name implies, is supposed to introduce your subject without extending it. All relevant information and facts should be placed in the body and conclusion, not the introduction.

Structure Of An Introduction

Before explaining how to write an introduction for a research paper , it’s necessary to comprehend a structure that will make your introduction stronger and more straightforward.

A Good Hook

A hook is one of the most effective research introduction openers. A hook’s objective is to stimulate the reader’s interest to read the research paper.  There are various approaches you may take to generate a strong hook:  startling facts, a question, a brief overview, or even a quotation. 

Broad Overview

Following an excellent hook, you should present a wide overview of your major issue and some background information on your research. If you’re unsure about how to begin an essay introduction, the best approach is to offer a basic explanation of your topic before delving into specific issues. Simply said, you should begin with general information and then narrow it down to your relevant topics.

After offering some background information regarding your research’s main topic, go on to give readers a better understanding of what you’ll be covering throughout your research. In this section of your introduction, you should swiftly clarify your important topics in the sequence in which they will be addressed later, gradually introducing your thesis statement. You can use some  The following are some critical questions to address in this section of your introduction: Who? What? Where? When? How? And why is that?

Thesis Statement

The thesis statement, which must be stated in the beginning clause of your research since your entire research revolves around it, is the most important component of your research.

A thesis statement presents your audience with a quick overview of the research’s main assertion. In the body section of your work, your key argument is what you will expose or debate about it. An excellent thesis statement is usually very succinct, accurate, explicit, clear, and focused. Typically, your thesis should be at the conclusion of your introductory paragraph/section.

Tips for Writing a Strong Introduction

Aside from the good structure, here are a few tips to make your introduction strong and accurate:

• Keep in mind the aim of your research and make sure your introduction supports it.
• Use an appealing and relevant hook that catches the reader’s attention right away.
• Make it obvious to your readers what your stance is.
• Demonstrate your knowledge of your subject.
• Provide your readers with a road map to help them understand what you will address throughout the research.
• Be succinct – it is advised that your opening introduction consists of around 8-9 percent of the overall amount of words in your article (for example, 160 words for a 2000 words essay). 
• Make a strong and unambiguous thesis statement.
• Explain why the article is significant in 1-2 sentences.
• Remember to keep it interesting.

Mistakes to Avoid in Your Introduction

Check out what not to do and what to avoid now that you know the structure and how to write an introduction for a research paper .

• Lacking a feeling of direction or purpose.
• Giving out too much.
• Creating lengthy paragraphs.
• Excessive or insufficient background, literature, and theory.
• Including material that should be placed in the body and conclusion.
• Not writing enough or writing excessively.
• Using too many quotes.

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Jessica Abbadia is a lawyer that has been working in Digital Marketing since 2020, improving organic performance for apps and websites in various regions through ASO and SEO. Currently developing scientific and intellectual knowledge for the community's benefit. Jessica is an animal rights activist who enjoys reading and drinking strong coffee.

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How to write an introduction for a research paper

Beginnings are hard. Beginning a research paper is no exception. Many students—and pros—struggle with how to write an introduction for a research paper.

This short guide will describe the purpose of a research paper introduction and how to create a good one.

What is an introduction for a research paper?

Introductions to research papers do a lot of work.

It may seem obvious, but introductions are always placed at the beginning of a paper. They guide your reader from a general subject area to the narrow topic that your paper covers. They also explain your paper’s:

• Scope: The topic you’ll be covering
• Context: The background of your topic
• Importance: Why your research matters in the context of an industry or the world

Your introduction will cover a lot of ground. However, it will only be half of a page to a few pages long. The length depends on the size of your paper as a whole. In many cases, the introduction will be shorter than all of the other sections of your paper.

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Why is an introduction vital to a research paper?

The introduction to your research paper isn’t just important. It’s critical.

Your readers don’t know what your research paper is about from the title. That’s where your introduction comes in. A good introduction will:

• Help your reader understand your topic’s background
• Explain why your research paper is worth reading
• Offer a guide for navigating the rest of the piece
• Pique your reader’s interest

Without a clear introduction, your readers will struggle. They may feel confused when they start reading your paper. They might even give up entirely. Your introduction will ground them and prepare them for the in-depth research to come.

What should you include in an introduction for a research paper?

Research paper introductions are always unique. After all, research is original by definition. However, they often contain six essential items. These are:

• An overview of the topic. Start with a general overview of your topic. Narrow the overview until you address your paper’s specific subject. Then, mention questions or concerns you had about the case. Note that you will address them in the publication.
• Prior research. Your introduction is the place to review other conclusions on your topic. Include both older scholars and modern scholars. This background information shows that you are aware of prior research. It also introduces past findings to those who might not have that expertise.
• A rationale for your paper. Explain why your topic needs to be addressed right now. If applicable, connect it to current issues. Additionally, you can show a problem with former theories or reveal a gap in current research. No matter how you do it, a good rationale will interest your readers and demonstrate why they must read the rest of your paper.
• Describe the methodology you used. Recount your processes to make your paper more credible. Lay out your goal and the questions you will address. Reveal how you conducted research and describe how you measured results. Moreover, explain why you made key choices.
• A thesis statement. Your main introduction should end with a thesis statement. This statement summarizes the ideas that will run through your entire research article. It should be straightforward and clear.
• An outline. Introductions often conclude with an outline. Your layout should quickly review what you intend to cover in the following sections. Think of it as a roadmap, guiding your reader to the end of your paper.

These six items are emphasized more or less, depending on your field. For example, a physics research paper might emphasize methodology. An English journal article might highlight the overview.

Three tips for writing your introduction

We don’t just want you to learn how to write an introduction for a research paper. We want you to learn how to make it shine.

There are three things you can do that will make it easier to write a great introduction. You can:

• Write your introduction last. An introduction summarizes all of the things you’ve learned from your research. While it can feel good to get your preface done quickly, you should write the rest of your paper first. Then, you’ll find it easy to create a clear overview.
• Include a strong quotation or story upfront. You want your paper to be full of substance. But that doesn’t mean it should feel boring or flat. Add a relevant quotation or surprising anecdote to the beginning of your introduction. This technique will pique the interest of your reader and leave them wanting more.
• Be concise. Research papers cover complex topics. To help your readers, try to write as clearly as possible. Use concise sentences. Check for confusing grammar or syntax . Read your introduction out loud to catch awkward phrases. Before you finish your paper, be sure to proofread, too. Mistakes can seem unprofessional.

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What is a "good" introduction?

Citing sources in the introduction, "introduction checklist" from: how to write a good scientific paper. chris a. mack. spie. 2018..

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This is where you describe briefly and clearly why you are writing the paper. The introduction supplies sufficient background information for the reader to understand and evaluate the experiment you did. It also supplies a rationale for the study.

• Present the problem and the proposed solution
• Presents nature and scope of the problem investigated
• Reviews the pertinent literature to orient the reader
• States the method of the experiment
• State the principle results of the experiment

It is important to cite sources in the introduction section of your paper as evidence of the claims you are making. There are ways of citing sources in the text so that the reader can find the full reference in the literature cited section at the end of the paper, yet the flow of the reading is not badly interrupted. Below are some example of how this can be done:     "Smith (1983) found that N-fixing plants could be infected by several different species of Rhizobium."     "Walnut trees are known to be allelopathic (Smith 1949,  Bond et al. 1955, Jones and Green 1963)."     "Although the presence of Rhizobium normally increases the growth of legumes (Nguyen 1987), the opposite effect has been observed (Washington 1999)." Note that articles by one or two authors are always cited in the text using their last names. However, if there are more than two authors, the last name of the 1st author is given followed by the abbreviation et al. which is Latin for "and others". 

From:  https://writingcenter.gmu.edu/guides/imrad-reports-introductions

• Indicate the field of the work, why this field is important, and what has already been done (with proper citations).
• Indicate a gap, raise a research question, or challenge prior work in this territory.
• Outline the purpose and announce the present research, clearly indicating what is novel and why it is significant.
• Avoid: repeating the abstract; providing unnecessary background information; exaggerating the importance of the work; claiming novelty without a proper literature search. 
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How to Write an Essay Introduction (with Examples)   

The introduction of an essay plays a critical role in engaging the reader and providing contextual information about the topic. It sets the stage for the rest of the essay, establishes the tone and style, and motivates the reader to continue reading. 

Table of Contents

What is an essay introduction , what to include in an essay introduction, how to create an essay structure , step-by-step process for writing an essay introduction , how to write an introduction paragraph , how to write a hook for your essay , how to include background information , how to write a thesis statement .

• Argumentative Essay Introduction Example: 
• Expository Essay Introduction Example 

Literary Analysis Essay Introduction Example

Check and revise – checklist for essay introduction , key takeaways , frequently asked questions .

An introduction is the opening section of an essay, paper, or other written work. It introduces the topic and provides background information, context, and an overview of what the reader can expect from the rest of the work. 1 The key is to be concise and to the point, providing enough information to engage the reader without delving into excessive detail. 

The essay introduction is crucial as it sets the tone for the entire piece and provides the reader with a roadmap of what to expect. Here are key elements to include in your essay introduction: 

• Hook : Start with an attention-grabbing statement or question to engage the reader. This could be a surprising fact, a relevant quote, or a compelling anecdote. 
• Background information : Provide context and background information to help the reader understand the topic. This can include historical information, definitions of key terms, or an overview of the current state of affairs related to your topic. 
• Thesis statement : Clearly state your main argument or position on the topic. Your thesis should be concise and specific, providing a clear direction for your essay. 

Before we get into how to write an essay introduction, we need to know how it is structured. The structure of an essay is crucial for organizing your thoughts and presenting them clearly and logically. It is divided as follows: 2  

• Introduction:  The introduction should grab the reader’s attention with a hook, provide context, and include a thesis statement that presents the main argument or purpose of the essay.  
• Body:  The body should consist of focused paragraphs that support your thesis statement using evidence and analysis. Each paragraph should concentrate on a single central idea or argument and provide evidence, examples, or analysis to back it up.  
• Conclusion:  The conclusion should summarize the main points and restate the thesis differently. End with a final statement that leaves a lasting impression on the reader. Avoid new information or arguments. 

Here’s a step-by-step guide on how to write an essay introduction: 

• Start with a Hook : Begin your introduction paragraph with an attention-grabbing statement, question, quote, or anecdote related to your topic. The hook should pique the reader’s interest and encourage them to continue reading. 
• Provide Background Information : This helps the reader understand the relevance and importance of the topic. 
• State Your Thesis Statement : The last sentence is the main argument or point of your essay. It should be clear, concise, and directly address the topic of your essay. 
• Preview the Main Points : This gives the reader an idea of what to expect and how you will support your thesis. 
• Keep it Concise and Clear : Avoid going into too much detail or including information not directly relevant to your topic. 
• Revise : Revise your introduction after you’ve written the rest of your essay to ensure it aligns with your final argument. 

Here’s an example of an essay introduction paragraph about the importance of education: 

Education is often viewed as a fundamental human right and a key social and economic development driver. As Nelson Mandela once famously said, “Education is the most powerful weapon which you can use to change the world.” It is the key to unlocking a wide range of opportunities and benefits for individuals, societies, and nations. In today’s constantly evolving world, education has become even more critical. It has expanded beyond traditional classroom learning to include digital and remote learning, making education more accessible and convenient. This essay will delve into the importance of education in empowering individuals to achieve their dreams, improving societies by promoting social justice and equality, and driving economic growth by developing a skilled workforce and promoting innovation. 

This introduction paragraph example includes a hook (the quote by Nelson Mandela), provides some background information on education, and states the thesis statement (the importance of education). 

This is one of the key steps in how to write an essay introduction. Crafting a compelling hook is vital because it sets the tone for your entire essay and determines whether your readers will stay interested. A good hook draws the reader in and sets the stage for the rest of your essay.  

• Avoid Dry Fact : Instead of simply stating a bland fact, try to make it engaging and relevant to your topic. For example, if you’re writing about the benefits of exercise, you could start with a startling statistic like, “Did you know that regular exercise can increase your lifespan by up to seven years?” 
• Avoid Using a Dictionary Definition : While definitions can be informative, they’re not always the most captivating way to start an essay. Instead, try to use a quote, anecdote, or provocative question to pique the reader’s interest. For instance, if you’re writing about freedom, you could begin with a quote from a famous freedom fighter or philosopher. 
• Do Not Just State a Fact That the Reader Already Knows : This ties back to the first point—your hook should surprise or intrigue the reader. For Here’s an introduction paragraph example, if you’re writing about climate change, you could start with a thought-provoking statement like, “Despite overwhelming evidence, many people still refuse to believe in the reality of climate change.” 

Including background information in the introduction section of your essay is important to provide context and establish the relevance of your topic. When writing the background information, you can follow these steps: 

• Start with a General Statement:  Begin with a general statement about the topic and gradually narrow it down to your specific focus. For example, when discussing the impact of social media, you can begin by making a broad statement about social media and its widespread use in today’s society, as follows: “Social media has become an integral part of modern life, with billions of users worldwide.” 
• Define Key Terms : Define any key terms or concepts that may be unfamiliar to your readers but are essential for understanding your argument. 
• Provide Relevant Statistics:  Use statistics or facts to highlight the significance of the issue you’re discussing. For instance, “According to a report by Statista, the number of social media users is expected to reach 4.41 billion by 2025.” 
• Discuss the Evolution:  Mention previous research or studies that have been conducted on the topic, especially those that are relevant to your argument. Mention key milestones or developments that have shaped its current impact. You can also outline some of the major effects of social media. For example, you can briefly describe how social media has evolved, including positives such as increased connectivity and issues like cyberbullying and privacy concerns. 
• Transition to Your Thesis:  Use the background information to lead into your thesis statement, which should clearly state the main argument or purpose of your essay. For example, “Given its pervasive influence, it is crucial to examine the impact of social media on mental health.” 

A thesis statement is a concise summary of the main point or claim of an essay, research paper, or other type of academic writing. It appears near the end of the introduction. Here’s how to write a thesis statement: 

• Identify the topic:  Start by identifying the topic of your essay. For example, if your essay is about the importance of exercise for overall health, your topic is “exercise.” 
• State your position:  Next, state your position or claim about the topic. This is the main argument or point you want to make. For example, if you believe that regular exercise is crucial for maintaining good health, your position could be: “Regular exercise is essential for maintaining good health.” 
• Support your position:  Provide a brief overview of the reasons or evidence that support your position. These will be the main points of your essay. For example, if you’re writing an essay about the importance of exercise, you could mention the physical health benefits, mental health benefits, and the role of exercise in disease prevention. 
• Make it specific:  Ensure your thesis statement clearly states what you will discuss in your essay. For example, instead of saying, “Exercise is good for you,” you could say, “Regular exercise, including cardiovascular and strength training, can improve overall health and reduce the risk of chronic diseases.” 

Examples of essay introduction 

Here are examples of essay introductions for different types of essays: 

Argumentative Essay Introduction Example:  

Topic: Should the voting age be lowered to 16? 

“The question of whether the voting age should be lowered to 16 has sparked nationwide debate. While some argue that 16-year-olds lack the requisite maturity and knowledge to make informed decisions, others argue that doing so would imbue young people with agency and give them a voice in shaping their future.” 

Expository Essay Introduction Example  

Topic: The benefits of regular exercise 

“In today’s fast-paced world, the importance of regular exercise cannot be overstated. From improving physical health to boosting mental well-being, the benefits of exercise are numerous and far-reaching. This essay will examine the various advantages of regular exercise and provide tips on incorporating it into your daily routine.” 

Text: “To Kill a Mockingbird” by Harper Lee 

“Harper Lee’s novel, ‘To Kill a Mockingbird,’ is a timeless classic that explores themes of racism, injustice, and morality in the American South. Through the eyes of young Scout Finch, the reader is taken on a journey that challenges societal norms and forces characters to confront their prejudices. This essay will analyze the novel’s use of symbolism, character development, and narrative structure to uncover its deeper meaning and relevance to contemporary society.” 

• Engaging and Relevant First Sentence : The opening sentence captures the reader’s attention and relates directly to the topic. 
• Background Information : Enough background information is introduced to provide context for the thesis statement. 
• Definition of Important Terms : Key terms or concepts that might be unfamiliar to the audience or are central to the argument are defined. 
• Clear Thesis Statement : The thesis statement presents the main point or argument of the essay. 
• Relevance to Main Body : Everything in the introduction directly relates to and sets up the discussion in the main body of the essay. 

Writing a strong introduction is crucial for setting the tone and context of your essay. Here are the key takeaways for how to write essay introduction: 3  

• Hook the Reader : Start with an engaging hook to grab the reader’s attention. This could be a compelling question, a surprising fact, a relevant quote, or an anecdote. 
• Provide Background : Give a brief overview of the topic, setting the context and stage for the discussion. 
• Thesis Statement : State your thesis, which is the main argument or point of your essay. It should be concise, clear, and specific. 
• Preview the Structure : Outline the main points or arguments to help the reader understand the organization of your essay. 
• Keep it Concise : Avoid including unnecessary details or information not directly related to your thesis. 
• Revise and Edit : Revise your introduction to ensure clarity, coherence, and relevance. Check for grammar and spelling errors. 
• Seek Feedback : Get feedback from peers or instructors to improve your introduction further. 

The purpose of an essay introduction is to give an overview of the topic, context, and main ideas of the essay. It is meant to engage the reader, establish the tone for the rest of the essay, and introduce the thesis statement or central argument.  

An essay introduction typically ranges from 5-10% of the total word count. For example, in a 1,000-word essay, the introduction would be roughly 50-100 words. However, the length can vary depending on the complexity of the topic and the overall length of the essay.

An essay introduction is critical in engaging the reader and providing contextual information about the topic. To ensure its effectiveness, consider incorporating these key elements: a compelling hook, background information, a clear thesis statement, an outline of the essay’s scope, a smooth transition to the body, and optional signposting sentences.  

The process of writing an essay introduction is not necessarily straightforward, but there are several strategies that can be employed to achieve this end. When experiencing difficulty initiating the process, consider the following techniques: begin with an anecdote, a quotation, an image, a question, or a startling fact to pique the reader’s interest. It may also be helpful to consider the five W’s of journalism: who, what, when, where, why, and how.   For instance, an anecdotal opening could be structured as follows: “As I ascended the stage, momentarily blinded by the intense lights, I could sense the weight of a hundred eyes upon me, anticipating my next move. The topic of discussion was climate change, a subject I was passionate about, and it was my first public speaking event. Little did I know , that pivotal moment would not only alter my perspective but also chart my life’s course.” 

Crafting a compelling thesis statement for your introduction paragraph is crucial to grab your reader’s attention. To achieve this, avoid using overused phrases such as “In this paper, I will write about” or “I will focus on” as they lack originality. Instead, strive to engage your reader by substantiating your stance or proposition with a “so what” clause. While writing your thesis statement, aim to be precise, succinct, and clear in conveying your main argument.  

To create an effective essay introduction, ensure it is clear, engaging, relevant, and contains a concise thesis statement. It should transition smoothly into the essay and be long enough to cover necessary points but not become overwhelming. Seek feedback from peers or instructors to assess its effectiveness. 

References  

• Cui, L. (2022). Unit 6 Essay Introduction.  Building Academic Writing Skills . 
• West, H., Malcolm, G., Keywood, S., & Hill, J. (2019). Writing a successful essay.  Journal of Geography in Higher Education ,  43 (4), 609-617. 
• Beavers, M. E., Thoune, D. L., & McBeth, M. (2023). Bibliographic Essay: Reading, Researching, Teaching, and Writing with Hooks: A Queer Literacy Sponsorship. College English, 85(3), 230-242. 

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How to write an introduction for a research paper

Writing an introduction for a research paper can be one of the hardest parts of the writing process. How do you get started? In this post, we discuss the components of an introduction and explore strategies for writing one successfully.

What is an introduction?

The introduction to a research paper provides background information or context on the topic. It also includes the thesis statement and signposts that let the reader know what you will cover in the rest of the paper.

Depending on the type of research paper that you’re writing, you may also include a brief state of the field in your introduction. You might also put that in a separate section, called a literature review. Before you tackle writing your introduction, be sure to consult the assignment guidelines for your paper.

How to write an introduction

An introduction provides an overview of your topic and any background information that your readers need to know in order to understand the context. It generally concludes with an explicit statement of your position on the topic, which is known as your thesis statement.

The opening section

Many papers begin with a hook: a short anecdote or scenario that draws the reader in and gives a hint of what the paper will cover. A hook allows you to capture your reader’s attention and provides an anchor for the context that you will provide in the bulk of the introduction.

Most of your introduction should be taken up with background information, but this doesn’t mean that you should fill your opening section with overly general statements. Instead, provide key pieces of information (like statistics) that a reader would need to know in order to understand your main argument.

The thesis statement

Towards the end of the introduction, you should state your thesis, preferably in the form of "I argue that..." or "This paper argues that..." or a similar phrase. Although it’s called a “thesis statement,” your thesis can be more than one sentence.

Finally, an introduction contains a brief outline or "signposts" of what the rest of the article will cover (also known as forecasting statements). You can use language like, “in what follows,” or “in the rest of the paper,” to signal that you are describing what you’ll do in the remainder of the paper.

Tips for writing an introduction

1. don’t rely on generalizations.

An introduction is not simply filler. It has a very specific function in a research paper: to provide context that leads up to a thesis statement.

You may be tempted to start your paper with generalizations like, “many people believe that...” or, “in our society...,” or a general dictionary definition, because you’re not sure what kind of context to provide. Instead, use specific facts like statistics or historical anecdotes to open your paper.

2. State your thesis directly

Once you’ve provided the appropriate, and specific, background information on your topic, you can move on to stating your thesis. As a rule of thumb, state your thesis as directly as possible. Use phrases like “I argue that..” to indicate that you are laying out your main argument.

3. Include signposts

A strong introduction includes clear signposts that outline what you will cover in the rest of the paper. You can signal this by using words like, “in what follows,” and by describing the steps that you will take to build your argument.

4. Situate your argument within the scholarly conversation

Some types of research papers require a separate literature review in which you explore what others have written about your topic.

Even if you’re not required to have a formal literature review, you should still include at least a paragraph in which you engage with the scholarly debate on your chosen subject. Be sure to include direct quotes from your sources . You can use BibGuru’s citation generator to create accurate in-text citations for your quotes.

This section can come directly before your thesis statement or directly after it. In the former case, your state of the field will function as additional context for your thesis.

Frequently Asked Questions about how to write an introduction for a research paper

A good introduction provides specific background information on your topic, sets up your thesis statement, and includes signposts for what you’ll cover in the rest of the paper.

An introduction should include context, a thesis statement, and signposts.

Do not include generalizations, apologies for not being an expert, or dictionary definitions in your introduction.

The length of your introduction depends on the overall length of your paper. For instance, an introduction for an 8-10 page paper will likely be anywhere from 1-3 pages.

You can choose to start an introduction with a hook, an important statistic, an historical anecdote, or another specific piece of background information.

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Starting Your Research Paper: Writing an Introductory Paragraph

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Writing the introductory paragraph can be a frustrating and slow process -- but it doesn't have to be.  If you planned your paper out, then most of the introductory paragraph is already written.  Now you just need a beginning and an end.

Here's an introductory paragraph for a paper I wrote.  I started the paper with a factoid, then presented each main point of my paper and then ended with my thesis statement.

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Introduction to legal research.

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Before you Begin

Good research, especially legal research, begins with knowing what it is you are researching. Never feel embarrassed to ask questions during any point of the legal research process. Relying on assumptions, rather than asking questions, may lead to errors in your research.

Understand the scope of the research project . Ensure you have a full understanding of the legal issue under research by taking thorough notes on the assignment. Carefully read, and reread, any materials related to the research project your professor provided.

Initial communications . Confirm your research project meets the expectations of the assignment by emailing or speaking to your professor. In addition, ask your professor if there are ways to improve your research project. Finally, do not forget to confirm the due date of the project.

Create and adhere to a timeline . You will want to create and adhere to a timeline to ensure adequate time is available for you to research a legal issue and to write your analysis. Performing at lease a little research each day is an easy way to adhere to a timeline. 

Continuing communications . Make certain to respond promptly to any communications from your professor. And if you have questions during your research, reach out to your professor to ask for assistance.

Suggested Research Strategy

Ask relevant questions .  Any research into legal matters should begin with a review of the facts of the case.  To make certain you have a thorough understanding of the details at hand, ask yourself the 5Ws: who, what, where, when, why.

Determine the jurisdiction . After you have established the necessary details of the legal issue, you will need to determine what jurisdiction is involved. Is the matter under research governed by federal or state law? For legal questions arising from the states, which state or states issued the law? For federal legal questions, you will need to determine the relevant Circuit and District courts .

Consult secondary sources .  Secondary sources are sources which analyze, critique, or discuss legal issues. In other words, these are resources about the law, not the law itself. Common forms of secondary sources include articles published within legal periodicals, legal dictionaries, and legal treatises.

Consult primary law . Primary law is the actual text of the law as issued by official government bodies. These laws include  statutes , cases , and  regulations . Constitutions , such as the U.S. Constitution , are also considered primary law.

Confirm your authority is still good law . Use a citator, such as Shepard's , in Nexis Uni , to confirm your case remains good law.

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• Published: 27 April 2021

Urbanization: an increasing source of multiple pollutants to rivers in the 21st century

• Maryna Strokal   ORCID: orcid.org/0000-0002-8063-7743 1 ,
• Zhaohai Bai   ORCID: orcid.org/0000-0001-7685-5441 2 ,
• Wietse Franssen 1 ,
• Nynke Hofstra 1 ,
• Albert A. Koelmans 3 ,
• Fulco Ludwig 1 ,
• Lin Ma   ORCID: orcid.org/0000-0003-1761-0158 2 ,
• Peter van Puijenbroek   ORCID: orcid.org/0000-0001-6370-2411 4 ,
• J. Emiel Spanier 1 ,
• Lucie C. Vermeulen   ORCID: orcid.org/0000-0002-8403-2442 5 ,
• Michelle T. H. van Vliet   ORCID: orcid.org/0000-0002-2597-8422 6 ,
• Jikke van Wijnen 7 &
• Carolien Kroeze 1  

npj Urban Sustainability volume  1 , Article number:  24 ( 2021 ) Cite this article

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Most of the global population will live in urban areas in the 21st century. We study impacts of urbanization on future river pollution taking a multi-pollutant approach. We quantify combined point-source inputs of nutrients, microplastics, a chemical (triclosan) and a pathogen ( Cryptosporidium ) to 10,226 rivers in 2010, 2050 and 2100, and show how pollutants are related. Our scenarios consider socio-economic developments and varying rates of urbanization and wastewater treatment. Today, river pollution in Europe, South-East Asia and North America is severe. In the future, around 80% of the global population is projected to live in sub-basins with multi-pollutant problems in our high urbanization scenarios. In Africa, future river pollution is projected to be 11–18 times higher than in 2010, making it difficult to meet Sustainable Development Goals. Avoiding future pollution is technically possible with advanced wastewater treatment in many regions. In Africa, however, clean water availability is projected to remain challenging. Our multi-pollutant approach could support effective water pollution assessment in urban areas.

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Current wastewater treatment targets are insufficient to protect surface water quality

Chemical pollution imposes limitations to the ecological status of European surface waters

Domestic waste emissions to European waters in the 2010s

Introduction.

Urban areas currently accommodate more than half of the global population 1 and generate over two-thirds of the world gross domestic products (GDP) 2 , 3 . In 2050, more than two-thirds of the global population will live in cities 1 , 4 , 5 . Rapid urbanization creates opportunities for economic developments 6 , but may also increase the use of freshwater resources 4 , 6 , 7 , 8 , 9 . This will increase competition for water between cities and agriculture 4 . More urban waste is likely to result in contamination of water with multiple pollutants such as nutrients 10 and pathogens 11 , 12 from human excretion, plastics 13 , 14 , 15 , 16 , 17 , 18 , and chemicals 19 , 20 from personal care products. River pollution poses a threat to the availability of clean water in large parts of the world 7 , 21 , challenging the achievement of Sustainable Development Goal 6 (SDG, clean water for all) and 11 (sustainable cities). Recent studies on impacts of rapid urbanization on water stress or water scarcity worldwide exist 4 , but often ignore water quality 7 .

Previous global studies likely underestimate the impact of urbanization on water pollution because of their strong focus on single pollutants 10 , 16 , 20 , 22 , 23 , 24 (Fig. 1 ). Urbanization (e.g., sewer connections in cities) is, however, often a common, point source of multiple pollutants in rivers, contributing to multiple impacts. Examples are eutrophication problems caused by nitrogen (N) and phosphorus (P) in many world regions 25 , 26 , and diarrhea caused by pathogens (e.g., Cryptosporidium ) especially in developing countries 11 , 27 . A multi-pollutant approach is, thus, urgently needed to account for interactions between drivers of urbanization (e.g., population, economy) and pressures such as emissions of different pollutants 21 . This can help to identify effective solutions accounting for synergies and trade-offs in pollution control. Furthermore, reducing multiple pollutants in rivers from urban-related sources might be easier (e.g., improved wastewater treatment) than from diffuse sources such as agricultural runoff (e.g., delay effects of reduction options due to accumulation of substances in soils). This may have a positive effect on the overall water quality status depending on diffuse sources.

The figure shows a difference between single-pollutant approaches (most existing studies) and a multi-pollutant approach (this study) to assess the impacts of the rapid urbanization on future global river quality. We take N (nitrogen), P (phosphorus), pathogens and plastics as examples. Advances of the multi-pollutant approach are discussed in the main text.

In this paper, we study the impacts of urbanization on river pollution in the 21st century, taking a multi-pollutant perspective. We define multi-pollutant problems as increasing levels of more than one pollutant to rivers in future decades. We analyze, simultaneously, the following groups of pollutants: nutrients (N and P), pathogens (such as Cryptosporidium ), microplastics and chemicals (such as triclosan). These pollutants are selected because of their increasing pollution in many rivers worldwide 18 , 20 , 23 , 28 , 29 , 30 . Yet, these pollutants have common urban sources such as sewer systems (worldwide) and open defecation. We quantify point-source inputs of the pollutants to 10,226 rivers for 2010, 2050 and 2100 associated with urbanization: sewer systems and open defecation. For this, we use a global model of Strokal et al. 31 that takes the sub-basin scale modelling approach of Strokal et al. 32 for nutrients and integrates modelling approaches for other pollutants 18 , 20 , 23 (Supplementary Tables 1 , 2 and 3 ). We develop this model further for multiple-pollutants and future analyses based on evaluated, modelling approaches (see the “Methods” section).

To assess the impacts of urbanization, we develop five scenarios with different levels of urbanization and wastewater treatment rates (Fig. 2 ). The storylines are interpretations of the five Shared Socio-economic Pathways (SSPs) 33 , 34 , 35 , 36 (Supplementary Tables 4 , 5 and 6 ). These SSPs are five pathways with different levels of socio-economic challenges for mitigation and adaptation 33 , 34 , 35 , 36 . SSP1 is a Green Road pathway with low socio-economic challenges (e.g., low population growth), but with high economic and urbanization development. It is largely oriented towards achieving sustainable goals (see Supplementary Tables 4 , 5 and 6 ). SSP2 is a middle of the road pathway with medium challenges to mitigation and adaptation. Future trends will not be very different from historical trends. SSP3 is a Rocky Road pathway with high challenges to mitigation and adaptation. It is a world with difficulties to control the population growth and has low economic and urbanization development (see Supplementary Tables 4 , 5 and 6 ). SSP4 is a Road Divided pathway with high challenges to mitigation and low to adaptation. It has a large gap between urban and rural development with the high urbanization rates especially in urban areas. SSP5 is a taking the highway pathway with high challenges to mitigate, but low challenges to adapt. It is a word with priorities towards economy (see Supplementary Tables 4 , 5 and 6 ).

Low, moderate and high urbanization is defined here as the increasing number of urban people and total people with sewer connections (see a and b panels and Supplementary Tables 4 – 6 ). The number of people opens defecating directly to water is assumed to decrease with sewer connection. Higher sewer connections imply that more wastewater treatment plants will be constructed to maintain the increasing volumes of the waste (see the “Methods” section). Low, moderate and high wastewater treatment levels refer here to a shirt (low, moderate, high) towards a next treatment type: e.g., from primary to secondary to tertiary ( a , b , Supplementary Tables 4 – 6 ). This implies the low, moderate and high ambitions to improve wastewater treatment ( b ). Future years are 2050 and 2100. Supplementary Tables 1 – 6 give quantitative interpretations of the storylines for our multi-pollutant model (see also the “Methods” section). GDP is the gross domestic product. Sources for the technologies are in the main text and in Supplementary Table 3 .

Our five scenarios incorporate socio-economic pathways of SSPs, but with quantitative interpretations of aspects related to urbanization and wastewater treatment (see the “Methods” section). Our scenarios aim to show the impact of urbanization on multiple pollutants in rivers. Thus, the names of our five scenarios correspond to the different levels of urbanization and wastewater treatment: from low urbanization and low wastewater treatment rates towards high urbanization and high wastewater treatment rates. This results in the following scenarios: low urbanization and low wastewater treatment rates (Low urb –Low wwt , based on SSP3), moderate urbanization and moderate wastewater treatment rates (Mod urb –Mod wwt , based on SSP2), high urbanization and low wastewater treatment rates (High urb –Low wwt , based on SSP4), high urbanization and moderate wastewater treatment rates (High urb –Mod wwt , based on SSP5), and high urbanization and high wastewater treatment rates (High urb –High wwt , based on SSP1) (Fig. 2 ). The five scenarios consider interactions between global change (socio-economic pathways), urbanization, sanitation and wastewater treatment.

Low, moderate and high urbanization reflect different levels of increases in urban population, and, indirectly, people with sewer connections between 2010 and future years (see the “Methods” section). As a net effect, the number of people practicing open defecation (direct inputs of human waste to rivers) may decrease. Increasing sewer connections assume higher capacities of treatment plants to manage increasing volumes of the wastewater. Low, moderate and high rates of wastewater treatment are defined based on a shift towards a next treatment type: e.g., from primary (technologies with <10% removal rates 10 , 18 , 20 , low) to secondary (50% removal rates 10 , 18 , 20 , 37 , moderate) or to tertiary (>75% removal rates 10 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , high, see the “Methods” section). The differences between the Low urb –Low wwt, and High urb –Low wwt scenarios indicate the impact of urbanization in terms of increasing numbers of people with sewer connections with low ambitions to improve the wastewater treatment under different socio-economic developments. The Mod urb –Mod wwt scenario could be considered business as usual. The differences between the High urb –Low wwt , High urb –Mod wwt and High urb –High wwt scenarios indicate the impact of improving the wastewater treatment in highly urbanized areas. Details are given in the “Methods” section on qualitative and quantitative descriptions of the five urbanization scenarios.

River pollution today

River pollution in Europe, South-East Asia and North America is already severe today. For these regions, we calculate high inputs of N (>50 kg km −2  year −1 ), P (>30 kg km −2  year −1 ), triclosan (>10 g km −2  year −1 ), microplastics (>5 kg km −2  year −1 ) and Cryptosporidium (>100 × 10 17 oocysts km −2 year −1 ) to many rivers in 2010 (Fig. 3 ). These regions experience severe water pollution problems 9 , 16 , 21 , 25 , 45 , contributing to negative impacts 21 such as eutrophication 45 and waterborne diseases (South-East Asian countries). For African sub-basins, pollution levels are not as high as in those regions (Fig. 3 ). However, some impacts of polluted water on children’s health are already indicated 21 . Globally, 9.5 Tg of N, 1.6 Tg of P, 0.45 Tg of microplastics, 0.72 kton of triclosan and 1.6 × 10 17 oocysts of Cryptosporidium entered rivers in 2010 (Fig. 4 , Supplementary Table 7 ). More than half of these inputs are to rivers in South-East Asia. Most of the pollutants in rivers are from sewer systems (see details in Supplementary Figs. from 1 to 29 ). Exceptions are some sub-basins in Africa and South-East Asia where open defecation contributes to over 20% of N, P and Cryptosporidium to their rivers. Existing assessments 9 , 10 , 13 , 20 , 23 reveal similar global estimates, but with diverse spatial scales. Our consistent spatial and temporal scales increase the robustness of our comparisons between multiple pollutants worldwide (e.g., Fig. 4 ).

Units are kg km −2 of sub-basin area year −1 for nitrogen (N), phosphorus (P) and microplastics (MP), g km −2 of sub-basin area year −1 for triclosan (TCS) and 10 17 oocysts km −2 of sub-basin area year −1 for Cryptosporidium . Source: the global multi-pollutant model (model description is provided in the “Methods” section, and in Supplementary Tables 1 – 6 , model inputs are in Supplementary Figs. 1 – 14 ). Model uncertainties are discussed in the “Methods” section.

a – e Future trends for individual pollutants. Pies show the shares of the surface areas by region as % of the global surface area. Spatially explicit results are shown in Fig. 3 for 2010 and Fig. 5 for the future. The description of the scenarios is in Fig. 2 , in the “Methods” section and Supplementary Tables 1 – 6 . Source: the global multi-pollutant model (model description is provided in the “Methods” section, and in Supplementary Tables 1 – 6 , model inputs are in Supplementary Figs. 1 – 14 ). Model uncertainties are discussed in the “Methods” section.

High pollution levels result from the net effect of population densities, sewer connection rates (Supplementary Figs. 1 , 2 and 3 ), production of pollutants in human waste (Supplementary Figs. 4 , 5 , 6 , 7 and 8 for individual pollutants) and wastewater treatment efficiencies (Supplementary Figs. 9 , 10 , 11 , 12 and 13 for individual pollutants) in countries (Supplementary Figs. 14 and 15 ). For South-East Asia, high pollution levels are driven by high population densities (Supplementary Figs. 3 and 16 ). This region accommodates approximately half of the global population (3 billion people, Supplementary Fig. 1 ) on 12% of the global surface area (Fig. 4 ). For comparison, sub-basins of Europe (excluding Russia) and North America accommodate around 10% of the global population (0.8 billion people, Supplementary Fig. 1 ) on 20% of the global surface area (Fig. 4 ). Approximately 20% of the total population in 2010 was connected to sewer systems (Supplementary Fig. 1 ) with relatively low wastewater treatment efficiencies (removal levels <50% for most pollutants, Supplementary Figs. 9 – 13 ). For Europe and North America, the high pollution levels per km 2 of sub-basins are driven by high connection rates to sewer systems especially in urban areas. Here, over two-thirds of the population live in urban areas and are largely connected to sewer systems with removal efficiencies above 50% for the studied pollutants (Supplementary Figs. 9 – 13 ). Supplementary Fig. 17 shows the results of the sensitivity analysis indicating the importance of wastewater treatment and human development in river pollution (see the “Discussion” section).

Future river pollution globally

In the future, ~80% of the global population is projected to live in sub-basins with multi-pollutant problems (Figs. 5 and 6 ). These sub-basins cover over half of the global surface area (Fig. 6 ) for which inputs of more than one pollutant will increase at least 30% (Fig. 5 ) between 2010 and 2050 or 2100. This is for all scenarios, except for High urb –High wwt . In the scenario assuming low urbanization and low wastewater treatment (Low urb –Low wwt ), global inputs of most pollutants will less than double between 2010 and 2050 (Fig. 4 ). In this scenario, the population growth is high, and almost doubles between 2010 and 2100 (Supplementary Fig. 3 ). Approximately one-third of the total population globally will be connected to sewer systems. This number is much lower than in the other scenarios in 2100 (Supplementary Fig. 3 ). As a net effect of the low sewer connection (Supplementary Fig. 3 ) and low wastewater treatment (Supplementary Figs. 9 – 13 ), future inputs of pollutants to rivers from sewage are lower in the Low urb –Low wwt scenario than in the others (Fig. 3 ). However, as a trade-off, more nutrients and Cryptosporidium are projected to enter rivers from open defecation, mainly in developing countries (see Supplementary Figs. 14 and 15 ) compared to the other scenarios.

Maps show changes in inputs of pollutants to rivers during the periods of 2010–2050, 2010–2100 and 2050–2100 according to the five scenarios. We classify sub-basins based on the number of pollutants for which the increases are higher or lower than 30% (Note: 30% is arbitrary; see Supplementary Figs. 18 and 20 for results based on 10 and 50% thresholds). The pollutants include Cryptosporidium , microplastic, triclosan, nitrogen and phosphorus. More information is available in Supplementary Figs. 18 – 29 . The description of the five scenarios is in Fig. 2 , in the “Methods” section and Supplementary Tables 1 – 6 . Results for 2010 are in Fig. 3 . Source: the global multi-pollutant model (model description is provided in the “Methods” section, and in Supplementary Tables 1 – 6 , model inputs are in Supplementary Figs. 1 – 14 ). Model uncertainties are discussed in the “Methods” section.

Sub-basins are classified based on the number of pollutants for which the increases are higher or lower than 30% during the periods of 2010–2050, 2010–2100 and 2050–2100 according to the five scenarios. Graphs show the number of sub-basins ( a ), sub-basin areas ( b ), total population ( c ) and urban population ( d ) for the sub-basins with the increases of higher or lower than 30% (Note: 30% is arbitrary; see Supplementary Figs. 19 and 21 for results based on 10% and 50% thresholds). More information is available in Supplementary Figs. 18 – 29 . See Fig. 5 for the changes in inputs of pollutants during the periods of 2010–2050, 2010–2100 and 2050–2100. The description of the scenarios is in Fig. 2 , in the “Methods” section and Supplementary Tables 1 – 6 . Results for 2010 are in Fig. 3 . Source: the global multi-pollutant model (model description is provided in the “Methods” section, and in Supplementary Tables 1 – 6 , model inputs are in Supplementary Figs. 1 – 14 ). Model uncertainties are discussed in the “Methods” section.

The future inputs of most pollutants to rivers are projected to be higher in the scenarios with moderate (Mod urb –Mod wwt ) and high urbanization (High urb –Low wwt , High urb –Mod wwt , Fig. 4 ). The population grows not as fast as in the Low urb –Low wwt scenario, but the rate of urbanization is much higher, especially in the High urb –Low wwt and High urb –Mod wwt scenarios (Supplementary Tables 4 – 6 ). As a result, over two-thirds of the global population is projected to be connected to sewer systems in 2100 (Supplementary Fig. 3 ). Wastewater treatment efficiency is slightly improved (Mod urb –Mod wwt , High urb –Mod wwt ) depending on the economic development (Supplementary Figs. 9 – 13 ). As a net effect, the High urb –Low wwt and High urb –Mod wwt scenarios project, generally, higher inputs of most pollutants to rivers than the Low urb –Low wwt and Mod urb –Mod wwt scenarios (Fig. 4 ).

Pollutants differ in their future trends. For example, High urb –Low wwt projects the highest inputs of Cryptosporidium , microplastics and triclosan globally in 2100 compared to the other pollutants and scenarios (Fig. 4 ). For N and P, High urb -Low wwt and High urb -Mod wwt project somewhat similar amounts globally (Fig. 4 ). All these differences between pollutants and scenarios are a net effect of three important factors: socio-economic development (e.g., population, GDP), urbanization rates (population connected to sewer systems) and treatment efficiencies. For example, higher GDP results generally in higher N and P excretion rates per capita because of changes towards protein-rich diets 31 , 46 (Supplementary Figs. 4 – 5 ). Developed countries (Human Developing Index, HDI > 0.785) have generally lower infection rates, leading to less per capita excretion of Cryptosporidium 23 (Supplementary Fig. 8 ), but may lead to higher production of microplastics from car tyres 31 (Supplementary Fig. 7 ) as a result of industrialization. All these interactions are considered together with different trends in the population growth (Supplementary Fig. 3 ), urbanization rates (Supplementary Figs. 1 and 2 ) and treatment levels (Supplementary Figs. 9 – 13 ) among scenarios and regions.

Future river pollution in Africa

Future river pollution is projected to be 11–18 times higher than in 2010 in the scenario with high urbanization and low wastewater improvements (High urb –Low wwt ). This range is for increasing inputs of the five pollutants by at least 30% during the period of 2010–2100 (Fig. 5 ). Africa may become a major contributor to river pollution in the world (Fig. 4 ). For example, by 2100, up to half of the global inputs of multiple pollutants are projected in Africa in High urb –Low wwt (Fig. 4 ). For comparison: in 2010 the contribution of African rivers to the global river pollution was <5% (Fig. 4 ). All scenarios project increasing river pollution in the future for Africa (Figs. 5 and 6 ). This is largely associated with the projected population growth and assumed wastewater treatment. The African population is projected to more than double in many sub-basins during 2010–2100 in all scenarios (Supplementary Fig. 3 ). Many people will live in urban areas (High urb –Low wwt and High urb –Mod wwt , Supplementary Figs. 1 – 3 ). More people will inevitably generate more waste, and this may not be treated effectively enough (e.g., High urb –Low wwt ). This all explains the large future increases in river pollution in Africa (Fig. 5 ). In the low urbanization scenario (Low urb –Low wwt ), less people will live in urban areas, and a lower percentage of people will be connected to sewer systems. Thus, open defecation may continue in Low urb –Low wwt especially by 2050. This is an important source of nutrients and Cryptosporidium to African rivers in this scenario. Supplementary Figs. 18 , 19 , 20 and 21 show results for increasing inputs of the five pollutants by at least 10% and 50% during the period of 2010–2100. Supplementary Figs. 22 , 23 , 24 , 25 and 26 show future trends in river pollution by individual pollutants. Supplementary Figs. 27 , 28 and 29 show scenarios and sub-basins where open defecation is an important source of P, N and Cryptosporidium in rivers.

Future river pollution in Asia

Future river pollution is projected to be 2–3 times higher than in 2010 in the scenario with high urbanization and low wastewater improvements (High urb –Low wwt ). This range is for at least 30% increases in inputs of the five pollutants for the period 2010–2100 (Fig. 5 ). Exceptions are rivers in sub-basins of China (Fig. 5 ). These rivers are projected to be cleaner in 2100 than in 2050, but inputs of the pollutants may still be higher in 2100 than in 2010 in the urbanized scenarios with the low (High urb –Low wwt and Low urb –Low wwt ) and moderate (Mod urb –Mod wwt and High urb –Mod wwt ) wastewater treatment improvements (Fig. 5 ). The Chinese population is projected to decrease in the future in all scenarios (Supplementary Fig. 3 ). However, with the rapid urbanization (Supplementary Figs. 1 – 2 ), the wastewater treatment (Supplementary Figs. 9 – 13 ) may not keep up with the pollution loads. This explains higher river pollution levels. This is different for some other Asian countries such as India and Pakistan. By 2050, the total population of India and Pakistan will have increased (Supplementary Fig. 3 ). By 2100, the total population will have decreased or increased depending on the socio-economic development in the scenarios (Supplementary Fig. 3 , Supplementary Tables 4 – 6 for the scenario description). However, the wastewater treatment is poorer or absent compared to the Chinese sub-basins (Supplementary Figs. 9 – 13 ), resulting in more pollutants in rivers (Fig. 5 , Supplementary Figs. 18 – 21 ).

Future river pollution in Europe and North America

Many rivers in Europe and North America may be cleaner in the future. European rivers (Western, Northern and Southern) may get cleaner in the future because of high removal efficiencies to treat wastewater (Supplementary Figs. 9 – 13 ). However, in the High urb –Mod wwt scenario, high wastewater treatment efficiencies (>50% for all pollutants) may not be enough to reduce future pollution to the level below 2010. For American rivers, future trends differ largely between South and North in the scenarios with the low (Low urb –Low wwt ) and high (High urb –Low wwt ) urbanization trends. In the Low urb –Low wwt scenario, lower increases (<30%) in inputs of pollutants are projected for many Northern rivers whereas higher increases (>30%) for most Southern rivers (Fig. 5 , Supplementary Figs. 18 – 21 ). This difference can be explained by the higher population growth (Supplementary Figs. 1 – 3 ) and less efficient wastewater treatment (Supplementary Figs. 9 – 13 ) in South America compared to North America. In the High urb –Low wwt scenario, higher increases in river pollution are projected for South America by 2050, but lower by 2100. This is associated with the decreased population (Supplementary Fig. 3 ) and with the increased efficiencies of wastewater treatment between 2050 and 2100 (Supplementary Figs. 9 – 13 ). Rivers in Australia may be more polluted in the future (Fig. 5 ). Exceptions are the Low urb –Low wwt and High urb –Low wwt scenarios with less pollution in 2100 than in 2050. This is largely associated with the decreasing population during 2050–2100 (Supplementary Figs. 1 – 13 , 18 – 21 ).

Reducing future river pollution

Advanced wastewater treatment can reduce future river pollution in many world regions, but not in Africa (High urb –High wwt ). In High urb –High wwt, all developed countries (HDI > 0.785) will shift completely towards tertiary treatment with enough capacities and high efficiencies to remove pollutants from the wastewater (>75% for all pollutants, Supplementary Figs. 1 – 14 ). Examples of such technologies are annomox 47 for N, calcium precipitation for P 48 , disinfection by Ultraviolet radiation for Cryptosporidium 42 , reverse osmosis for nutrients 41 and microplastics 49 . Developing countries (HDI < 0.785) will also shift towards tertiary technologies, but in combination with secondary technologies 10 , 46 (Supplementary Figs. 1 – 14 ). Open defecation will stop by 2100. Thus, High urb –High wwt shows the technical potential of advanced technologies with enough treatment capacities to reduce future pollution from highly urbanized areas.

It will be difficult to reduce future river pollution in Africa to the level of 2010, even with advanced technologies (High urb –High wwt , Fig. 5 ). Inputs of most pollutants to many African rivers are projected to increase by at least 30% during 2010–2100 in High urb –High wwt (Fig. 5 ). The main reason is an increase in the total population, which is much higher (>doubling) than in other world regions (Supplementary Fig. 3 ). As a result, implementing advanced technologies in 2100 may help to reduce inputs of most pollutants to the level of 2050, but not to the level of 2010. For many other world’s rivers, advanced technologies with enough treatment capacities are projected to lower future inputs of pollutants in High urb –High wwt (Fig. 5 , Supplementary Fig. 20 ). This may have a positive impact on the overall pollution status depending also on the contribution of diffuse sources from agriculture. However, for some rivers in Asia (e.g. India, Pakistan), inputs of most pollutants from point sources will still increase by 2050, but may be lower by 2100 in High urb –High wwt (Fig. 5 ). Some rivers in North America, Middle Asia and Australia are projected to have higher inputs of pollutants in 2100 than in 2050, but lower than in 2010 (Fig. 5 , Supplementary Fig. 20 ). These trends are the net effect of the population growth, urbanization and wastewater treatment in High urb –High wwt (Figs. 2 , 5 and 6 ).

Scenario analyses are widely used to explore possible futures 1 , 34 , 36 , 50 , 51 , 52 . Our five scenarios are a combination of possible trends in urbanization, socio-economic development (existing SSPs 1 , 36 , 53 ) and our assumptions on sanitation, wastewater treatment capacities and removal efficiencies of pollutants. Our assumptions may, however, seem ambitious (Supplementary Tables 5 and 6 ). For example, we assume the full implementation of advanced technologies with enough treatment capacities in High urb –High wwt for all developed countries. We did this to show the effects of sustainable practices in urban areas on increasing the availability of clean water for people and nature. This assumption, however, might be ambitious to achieve. In our scenarios, we reflect a relation between urbanization (e.g., more urban people) and sewer connections (see High urb –Low wwt, High urb –Med wwt ) with sustainable urbanization practices (see High urb –High wwt ). This relation may, however, not emerge everywhere in the world. On the other hand, we explore possible futures; we do not state how likely or desirable these futures are. Our scenarios aim to identify impacts of future urbanization (e.g., differences between Low urb –Low wwt and High urb –Low wwt ) and the technical potentials of proven wastewater treatment technologies to reduce future river pollution from point sources (e.g., differences between High urb –Low wwt and High urb –High wwt ). Our insights may contribute to the formulation of sustainable urbanization practices where wastewater treatment is effective enough to reduce pollutants in the urban waste (e.g., SDG11) and thus to increase the availability of clean water in the future (e.g., SDG6).

Our global multi-pollutant model quantifies, simultaneously, five pollutants in rivers with consistent datasets in space and time. However, uncertainties exist. The model is developed based on existing, evaluated models for pollutants 11 , 18 , 20 , 23 , 29 , 32 (e.g., comparisons with observed concentrations and sensitivity analyses). We further evaluate our combined model using five approaches 54 (see the “Methods” section). First, we compare our model outputs with existing studies (see the “Methods” section, Supplementary Table 7 ), showing a good agreement for the five pollutants. Second, we compare the spatial pattern of pollution problems with existing models 8 , 9 , 10 , 11 , 12 , 16 , 55 , 56 , indicating the river pollution in densely populated and highly urbanized areas (Figs. 3 – 5 , Supplementary Tables 7 and 8 ). However, existing studies did not focus on a simultaneous reduction of the five pollutants from urbanized activities in the 21st century, which is a multi-pollutant perspective of our study. Third, we performed a sensitivity analysis for pollution hotspots. We define multi-pollutant hotspots as places with >30% increases in two or more pollutants between 2010 and future years (Fig. 5 ). This is an elegant way to combine the five pollutants. We realize that the 30% threshold is arbitrary. The results should, therefore, be interpreted as warning signals of future river pollution. In the sensitivity analysis, we changed the 30% threshold to 10% (Supplementary Figs. 18 – 19 ) and 50% (Supplementary Figs. 20 – 21 ). The results confirm the robustness of our main messages about future multi-pollutant hotspots. Fourth, we performed a sensitivity analysis for all important model inputs underlying the calculations (Supplementary Tables 9 , 10 , 11 and 12 , Supplementary Fig. 17 ). In total, 25 model inputs are changed with ±10%, resulting in 50 model runs for 10,226 sub-basins and five pollutants. The results show that the model is not very sensitive to changes in most model inputs. For most sub-basins, the model outputs are relatively sensitive to changes in <5 model inputs. These inputs are related to HDI, wastewater treatment types and removal efficiencies. The 10% changes in these inputs, resulted in up to 5% change in model output for sub-basins covering over two-thirds of the global surface area (see details in the “Methods” section for all sub-basins). Fifth, we compare model inputs with independent datasets (Supplementary Table 8 , Supplementary Figs. 15 and 16 ). All this gives trust in the model performance (see the “Methods” section).

Our results are future oriented. We focus on trends in future hotspots of multi-pollutant problems in the world. We believe that not all model uncertainties affect our main messages about trends. We also realize that our results are relatively sensitive to the assumptions on future HDI and wastewater treatment (see Approach 4 in the “Methods” section and sensitivity analysis). For HDI, we assumed an increase of 0, 10 and 20% between 2010 and 2050 and further increase by 2100 depending on scenario (Supplementary Tables 5 – 6 ). For wastewater treatment rates, we assumed a shift towards a next treatment type between 2010 and future years (e.g., 0–50% shift depending on scenario). To increase trust in our assumptions for future trends, we compared our model inputs with other independent studies. We did this for our five scenarios (Supplementary Table 8 , Supplementary Fig. 15 ). For example, future trends in our HDI between 2010 and future years are strongly in line with an independent study 57 ( R 2 above 0.88, see Supplementary Fig. 15 ). Crespo Cuaresma and Lutz 57 took into account differences in human development and their socio-economic wealth in projecting future HDI. Our wastewater treatment types in 2050 are also well compared with an independent study 10 (Supplementary Table 8 ).

Another potential source of uncertainties relates to the local variation in pollution levels. For example, sewage overflows may happen under heavy rain events, causing local peaks in water pollution. Such events are time dependent and may also contribute to global pollution levels 58 . We do not account for such local events in our model. We, however, believe that such omissions of events do not affect our messages for the multi-pollutants worldwide. This is because we explore future trends in the multi-pollutant hotspots worldwide that are influenced by global change, urbanization and wastewater treatment. Local analyses should, however, account for the impact of local events on local water quality (e.g., cities).

Our study aims to analyze the impact of the socio-economic drivers (e.g., GDP) and urbanization on future inputs of pollutants to rivers from point sources worldwide. However, we do not consider the transport of pollutants to rivers from agricultural fields, nor the impact of climate change on future river pollution. Next steps could be to further develop our global multi-pollutant model by calculating inputs of pollutants from agricultural fields and associated river export of pollutants. This will allow to explicitly combine the impact of both climate change and of socio-economic developments.

A multi-pollutant approach supports the search for effective solutions. A multi-pollutant approach might be more effective in reducing river pollution than a single-pollutant approach (Fig. 1 ). For example, reducing one pollutant may reduce (synergies) or increase (trade-offs) another pollutant. Our study serves as an illustrative example for the five pollutants. For example, increasing sewer connections may increase inputs of the five pollutants to rivers, but decrease inputs of N, P and Cryptosporidium from open defecation (Low urb –Low wwt ; trade-off). Higher economic developments may lead to less excreted Cryptosporidium per capita because of lower infection risks in developed countries 11 , 23 (Supplementary Fig. 8 ), but may generate more N and P in human excreta (Supplementary Figs. 4 – 5 ) as a result of protein-rich food consumption 10 , 46 (trade-off). Synergies also exist. For example, increasing sewer connections with advanced technologies and sufficient wastewater treatment capacities is projected to decrease the inputs of all five pollutants to many rivers in the future (High urb –High wwt ). This is also associated with synergies in treatment technologies to remove multiple pollutants. Some technologies are developed to target specific pollutants (e.g., N 47 , P 48 , Cryptosporidium 42 ). This implies that implementing technologies for one pollutant may not strongly influence another pollutant. However, technologies exist to treat more than one pollutant (e.g., 10 , 38 , 39 , 40 , 42 , 59 ). For example, secondary treatment with removal efficiencies of around 40–50% (assumed in Mod urb –Mod wwt and High urb –Mod wwt ) converts organic N into inorganic and gas, removing N from the waste 10 . They can also facilitate the biodegradation of triclosan 59 . Microplastics can host microorganisms (e.g., Cryptosporidium ) and serve as vectors for chemicals 15 , 49 , 60 . As a result, biofilms and flocs can form in, for example, activated sludge ponds and then settle down 49 . Triclosan can sorb to large particles and also settle down with other pollutants 38 , 39 , 59 . Advanced technologies (assumed in High urb –High wwt ) such as efficient ultrafiltration methods can reduce Cryptosporidium 42 and microplastics 49 , and reverse osmosis can recover nutrients 41 and reduce microplastics 49 . Nature-based solutions such as stabilization ponds and constructed wetlands are largely effective to reduce Cryptosporidium 42 and nutrients 61 . Accounting for synergies and trade-offs is essential to identify effective solutions for multiple pollutants. This can support the achievement of SDG11 for sustainable cities and SDG6 for clean water.

Our results can support policy assessment of water pollution in urban areas, and form the basis for actionable and region-specific solutions. We identify hotspots of urban-related river pollution and show possible effects of future urbanization on river quality under global change. This could help to prioritize short-term actions to avoid river pollution in the 21st century. Improving wastewater treatment is important to avoid multi-pollutant problems in an urbanized world (Fig. 5 , differences between High urb –High wwt and High urb –Low wwt ). Our sensitivity analysis indicates where improved wastewater treatment could have a larger impact (Supplementary Fig. 17 ). Our model indicates that water pollution is related to human development (expressed as human development index). This is important to realize when reducing Cryptosporidium and microplastics. Some countries in the world already introduced policies such as a ban of detergents and triclosan in products. Combing such policies with improved wastewater treatment may contribute to synergetic solutions for achieving SDGs and reducing river pollution from urban waste. For Africa, improving wastewater treatment may not be enough. Controlling the African population growth to reduce waste production in the future may be needed in urban and water policy assessments.

Our study quantifies future trends in inputs of five pollutants to rivers for five scenarios. We argue that a multi-pollutant perspective is needed in quantitative analyses of future trends in global change, urbanization, sanitation and wastewater treatment. We analyzed multiple pollutants simultaneously in a consistent way. We did this for 10,226 sub-basins for 2010, 2050 and 2100. Our insights are in how future trends differ between pollutants, sub-basins and how hotspots of multi-pollutant problems change in the 21st century. Our study provides an example of multi-pollutant problems from urban point sources. We show that future inputs of pollutants are projected to increase with increasing urbanization. We also show that it is technically possible to avoid these increases with advanced proven technologies to treat wastewater, except in Africa. In Africa, clean water availability is projected to remain a challenge because of the fast increasing population. This will consequently challenge the achievement of SDGs 6 and 11 in Africa. Our model may serve as an example for multi-pollutant modelling of diffuse sources such as agricultural runoff and other pollutants, such as pesticides 62 , antibiotics 24 and antimicrobial resistance. Another opportunity is to analyze the economic (e.g., costs), societal, institutional and political feasibilities of future pollution reduction options. This is important to identify region-specific solutions. Our long-term projections can help to increase the awareness of society and decision makers about pollution hotspots in the 21st century. This can facilitate short-term actions in different regions to avoid pollution in the future and contribute to achieve SDGs 6 and 11.

Model description and inputs

We used a model of Strokal et al. 31 that takes the sub-basin scale modelling approach of Strokal et al. 32 for nutrients and integrates modelling approaches for other pollutants 18 , 20 , 23 . We developed it further for future analyses of point-source inputs of pollutants to rivers (Supplementary Table 1 ). Our model quantifies inputs of five pollutants to 10,226 rivers: nitrogen (N), phosphorus (P), microplastics, triclosan and Cryptosporidium for 2010, 2050 and 2100. The model of Strokal et al. 31 was developed for 2010 taking the sub-basin modelling approach of Strokal, et al. 32 for N 29 , 32 , P 29 , 32 and integrating the existing modelling approaches for microplastics 18 , triclsan 20 and Cryptosporidium 23 . We developed the model for the years 2050 and 2100 based on the urbanization storylines of the SSPs and our assumptions. Our multi-pollutant model quantifies simultaneously annual inputs of the five pollutants to rivers at the sub-basin scale using the consistent spatial and temporal dataset for model inputs for 2010, 2050 and 2100. The model quantifies inputs of the five pollutants from sewer systems and open defecation. These are the point sources of the pollutants in rivers. Sewer systems discharge five pollutants to rivers. Open defecation is a point source of N, P and Cryptosporidium in our model. Model evaluation is presented below after the scenario descriptions.

Inputs of the pollutants to rivers from open defecation are quantified as a function of the population that is open defecating and the excretion or consumption rates of pollutants per person per year (Supplementary Tables 1 and 2 ). Inputs of pollutants from sewer systems are quantified as a function of the population that is connected to sewer systems, the excretion or consumption rates of pollutants per person per year and removal efficiencies of pollutants during treatment. We quantified inputs of the pollutants at 0.5° grid and then aggregate the results to 10,226 river sub-basins (Supplementary Table 1 ). Model inputs for 2010 are directly from Strokal, et al. 31 . Model inputs for 2050 and 2100 are based on the SSPs with different trends in urbanization and wastewater treatment (see scenario descriptions below).

Below, we explain how model inputs were derived (Supplementary Tables 1 – 6 ). Population for 2010, 2050 and 2100 are aggregated to 0.5° grid from the global, 0.125 degree cell database of Jones and O’Neill 53 . The number of people with sewer connections and open defecation are quantified at 0.5° grid using the population map of 0.5° grid and the fraction of people with sewer connections or open defecation. For 2010, the fraction of urban and rural people with sewer systems and open defecation were available by country from the Joint Monitoring Program (see details in Strokal et al. 31 and Hofstra and Vermeulen 11 ). We assigned the national values to grids of 0.5° grid. Then, we multiplied the number of people per grid (aggregated from Jones and O’Neill 53 ) with the fraction of people connected to sewer systems or open defecating (based on Hofstra and Vermeulen 11 ). For 2050 and 2100, we made assumptions for the fractions of people connected to sewer systems and with open defecation. These assumptions were based on storylines of SSPs for economy, population and urbanization (Fig. 2 , Supplementary Tables 4 – 6 ). Our assumptions differ among urban and rural people, and among developing and developed countries (see scenario descriptions below).

Excretion or consumption rates of pollutants were largely derived based on existing, evaluated approaches and sources. Excretion rates of N and P in human waste per person are quantified as a function of GDP (gross domestic product) at purchasing power parity, following the approach of Van Drecht et al. 46 , but adjusted to the unit of 2005 (see details in Strokal et al. 31 , Supplementary Tables 1 – 6 ). For 2010, 2050 and 2100, GDP at 0.5° grid was derived from the global SSP database with the projections from the International Institute for Applied Systems Analysis (IIASA, 63 ). P in detergents was from Van Drecht et al. 46 for the world regions (Supplementary Tables 1 – 6 ).

Excretion rates of Cryptosporidium were quantified based on the infection rate in developed (5%) and developing (10%) countries and the excretion rate per ill person (10 9 oocysts) according to Hofstra et al. 23 . For 2010, developed and developing countries were defined based on the Human Development Index (HDI), following the approach of Hofstra et al. 23 : HDI > 0.785 (developed) and HDI < 0.785 (developing). For 2050 and 2100, we made assumptions for HDI for countries depending on SSP storylines for the economy, population growth and urbanization (see scenario descriptions below and Supplementary Tables 4 – 6 ).

Consumption rates of microplastics per person per year were derived directly from Siegfried et al. 18 , but with some modifications (details are in Strokal et al. 31 ). Microplastics in sewer systems result from car tyres, PCPs (personal care products), household dusts and laundry. For PCPs, dust and laundry, consumption rates are 0.071, 0.08 and 0.12 kg of microplastics per person per year according to Siegfried, et al. 18 . We assumed that these values do not change over time. For tyres, this is different. Strokal et al. 31 assumed that developed countries will contribute more microplastics to sewage from car tyres as a side-effect of economic and infrastructural developments. Thus, we assigned 0.18 kg of microplastics from tyres per person for developed countries (HDI > 0.785) and 0.018 kg of microplastics from tyres per person for developing countries (HDI < 0.785) according to Strokal et al. 31 . We assumed changes in HDI by country in the future based on the SSPs storylines (see scenario descriptions below and Supplementary Tables 1 – 6 ).

Consumption rates of triclosan per person in the world were directly taken van Wijnen et al. 20 (0.5 kg per person per year for 2010). We assumed that the consumption rate will not change largely in the future and thus will remain as in 2010.

Removal efficiencies of pollutants during treatment were derived based on the existing studies. For N, P and Cryptosporidium , removal efficiencies were quantified by country using the national distribution of wastewater treatment types (primary, secondary, tertiary, no treatment) and their treatment efficiencies for pollutants, following the approaches of 11 , 23 , 46 (see Supplementary Tables 1 – 6 , Supplementary Figs. 1 – 14 ). The quantified national removal efficiencies were then assigned to corresponding grids of 0.5°. For 2010, national distributions of wastewater treatment types were derived from Hofstra and Vermeulen 11 with a few corrections for countries with missing data (details are in Strokal et al. 31 ). For 2050 and 2100, we assumed changes (low, moderate, high) in the distribution of the treatment types depending on the storylines of SSPs (see scenario descriptions below). These changes imply a shift towards a next treatment type: e.g., from primary to secondary to tertiary (Supplementary Tables 1 – 6 ). Removal efficiencies of pollutants for different treatment types were taken directly from literature (see Supplementary Table 3 ) and do not vary among years.

For triclosan and microplastics, removal efficiencies were quantified based on the approaches of van Wijnen et al. 20 and Siegfried et al. 18 (details are in Strokal et al. 31 ). We used the known removal rate of phosphorus to assume the removal of triclosan and microplastics. For our assumptions, we used data about the removal of triclosan and microplastics from literature 39 , 59 , 64 , 65 , 66 . Based on these data, we related average phosphorus removal in a watershed to triclosan removal. We formulated three classes of triclosan removal (0, 60 or 90%) and related these to known phosphorus removal in each sub-basin (details are in van Wijnen et al. 20 ). A similar approach was carried out for microplastics. We formulated four microplastics removal classes based on literature and related those to the known average phosphorus removal in each sub-basin 18 , 30 . These classes represent an average microplastics removal in each sub-basin. Microplastic removal depends on the size and density of the microplastics. Therefore, the removal at each individual WWTP will be dependent on these and other characteristics. In our study, on a global scale, we chose to assume average removal for each sub-basin.

Scenario description

Storylines of the five scenarios are summarized in Fig. 2 , Supplementary Tables 1 – 6 and Supplementary Figs. 1 – 14 . Our five scenarios are with low urbanization and low wastewater treatment rates (Low urb –Low wwt ), moderate urbanization and moderate wastewater treatment rates (Mod urb –Mod wwt ), high urbanization and low wastewater treatment rates (High urb –Low wwt ), high urbanization and moderate wastewater treatment rates (High urb –Mod wwt ), and high urbanization and high wastewater treatment rates (High urb –High wwt ) (Fig. 2 ). These scenarios follow future trends in the socio-economic development based on the existing SSPs 1 , 63 , combined with our assumptions for population with sewer connections, open defecation and for wastewater treatment capacities and technologies (Supplementary Tables 4 – 6 ). Below, we describe each scenario. Quantitative interpretations of the scenario assumptions are presented in Supplementary Tables 4 – 6 for 2050 and 2100, and inputs are given in Supplementary Figs. 1 – 14 .

The Low urb -Low wwt scenario is based on SSP3 projections for the socio-economic development (Fig. 2 , Supplementary Tables 4 – 6 ). The scenario assumes a fragmented world with difficulties to control population growth. In this world, It is projected a low economic development with low urbanization rates and high population growth. For example, a global population of approximately 12 billion people is projected for 2100, of which 58% will be urban (Supplementary Figs. 1 – 3 ). Low economic developments will not allow to develop technologies largely. For 2050, HDI is assumed to stay as in 2010 and increase by 10% between 2050 and 2100 on a county level (Supplementary Tables 4 – 6 ). The society will not focus on reducing or avoiding future river pollution. As a result, the fraction of the population with sewer connections (around one-third of the global population) and the treatment efficiencies of wastewater (e.g., 14–18% globally depending on pollutant) will remain in 2050 as in 2010 (Supplementary Figs. 3 , 9 – 13 ). The same holds for the wastewater treatment capacities. However, by 2100 more people may be connected to sewer systems (above one-third of the global population). This will result in higher capacities of the wastewater treatment plants with slightly improved treatment technologies (e.g., 21–24% of removal efficiencies globally depending on pollutant). However, future wastewater treatment efficiencies vary largely among world countries: e.g., 0–96% in 2100 depending on region and pollutant. In general, higher wastewater treatment efficiencies are projected for Europe, North America and Australia (Supplementary Figs. 9 – 13 ),

The Mod urb -Mod wwt scenario is based on SSP2 projections of the middle of the road for the socio-economic development (Fig. 2 , Supplementary Tables 4 – 6 ). The scenario assumes a moderate economic development, moderate urbanization rates and moderate population growth compared to the other scenarios. For example, 9 billion people are projected globally for 2100 and 80% will be urban (Supplementary Figs. 1 – 3 ). From 2010, HDI is assumed to increase by 10% by 2050 and further increase by 10% by 2100 on a county level (Supplementary Tables 4 – 6 ). Technological development follows the business as usual trends. As a result, more people will be connected to sewer systems than today (45% in 2050 and 68% in 2100 globally, Supplementary Fig. 3 ). A number of wastewater treatment plants will be constructed to maintain the increasing volume of the wastewater from connected population to sewer systems. The amount of waste that is collected will be treated with slightly improved wastewater treatment. For example, on average, 33–42% of removal efficiencies globally are projected for 2100. This range is for the five pollutants. The removal efficiencies vary largely among regions (0–97% depending on region and pollutant, Supplementary Figs. 9 – 13 ). The number of people connected to sewer systems will be larger for urban (over two-thirds) than for rural (less than one-third) population. Some people may still experience open defecation in 2050. By 2100, all people who opened defecated in 2050 will become connected to sewer systems.

The High urb -Low wwt scenario is based on SSP4 projections for the socio-economic development (Fig. 2 , Supplementary Tables 4 – 6 ). The scenario assumes a large gap between urban and rural developments. The economic development is projected to be moderate compared to the other scenarios. HDI is projected to increase as in the Mod urb –Mod wwt scenario (Supplementary Tables 1 – 3 , Supplementary Fig. 14 ). The population is projected to increase in the future, but not largely: e.g., around 30% between 2010 and 2100 globally. By 2100, the global population is projected to reach 9.3 billion people (Supplementary Fig. 3a ). However, the urban population will develop faster than the rural. Urbanization will be high: e.g., 76% and 90% of the global population will be urban in 2050 and 2100, respectively. As a result, the connection rate of the population to sewer systems will increase in the future for urban areas. For example, 80% of urban and 11% of rural population globally is projected to be connected to sewer systems in 2100 (Supplementary Figs. 1 – 3 ). Wastewater treatment capacities will be enough to maintain the waste from sewer systems and treatment will be improved as in the Mod urb -Mod wwt scenario. For rural areas, the fraction of people connected to sewer systems in 2050 may remain the same as in the Low urb -Low wwt scenario and will be improved by 2100 (Supplementary Tables 4 – 6 ). By 2050, some rural people may still open defecate. By 2100, all rural people who opened defecated in 2050 will become connected to sewer systems with better treatment.

The High urb –Mod wwt scenario is based on SSP5 projections for the socio-economic development (Supplementary Tables 4 – 6 , Fig. 2 ). The scenario assumes a high economic development with high urbanization and low population growth (Fig. 2 , Supplementary Table 4 ). For example, the total population globally is projected to increase by less than 10% between 2010 and 2100, reaching 7.4 billion people in 2100 (Supplementary Fig. 3a ). However, more than 90% of the global population will be urban in 2100. From 2010, HDI is assumed to increase by 20% by 2050 and further increase by 20% by 2100. The technological development is relatively high compared to the Mod urb -Mod wwt scenario. This will lead to a higher population with sewer connections. More than half of the global population will be connected to sewer systems in 2050. For 2100, this number is over two-thirds of the global population (Supplementary Figs. 1 – 3 ). The capacities of the wastewater treatment plants will be enough to manage the amount of waste from sewer systems. However, people will invest less in improving wastewater treatment. People will focus more on the economy rather than on reducing river pollution. As a result, wastewater treatment may follow the business as usual trends. For example, on average, 34–44% of the wastewater treatment efficiencies are projected globally for 2100. However, these efficiencies vary largely among regions (0–97% depending on area and pollutant, Supplementary Figs. 9 – 13 ). Furthermore, some people may still open defecate in nearby water systems in the future. By 2100, all people who opened defecated in 2050 will become connected to sewer systems.

The High urb –High wwt scenario is based on SSP1 projections for the socio-economic development (Fig. 2 , Supplementary Tables 4 – 6 ). The society will develop fast with high urbanization rates as comparable to the High urb –Mod wwt scenario. The global population is projected to reach 6.9 billion people in 2100 (Supplementary Fig. 3a ). The share of urban people globally is projected to be 77% in 2050 and 92% in 2100 (Supplementary Figs. 1 – 3 ). The share of the total connected people to sewer systems is projected to be 55% in 2050 and 82% in 2100. HDI is projected to increase in the same rate as in the High urb –Mod wwt scenario. However, in this world, a strong focus is on reducing or avoiding river pollution by using the best available advanced technologies in all areas. Technological development is high because of the high economic development. People will invest in improving technologies to treat wastewater with multiple pollutants. There will be opportunities to develop technologies for multiple pollutants and combine them with nature-based solutions. As a result, the wastewater treatment is assumed to be improved largely with high removal efficiencies (60–98% depending on year, area and pollutant, Supplementary Figs. 9 – 13 ).

Model evaluation

We evaluated the uncertainties in our model using four approaches following a building trust circle method 54 . This method has been applied in several water quality studies 32 , 67 , 68 . First, we compare model outputs with existing studies. Second, we compare the spatial pattern of the pollution problems with existing models for individual pollutants. Third, we perform a sensitivity analysis for pollution hotspots. Fourth, we perform a comprehensive sensitivity analysis for all important model inputs underlying the calculations. Fifth, we compare model inputs with independent datasets. Model validation against observed concentrations is, unfortunately, challenging. This is because our model does not quantify concentrations. Some of the existing global models calculate concentrations and were evaluated against observations (Supplementary Tables 7 – 8 ). Thus, we used those models to compare their results with ours for individual pollutants. Below, we elaborate on these five approaches. Details are in Supplementary Tables 7 – 12 and Supplementary Figs. 15 , 17 .

Approach 1: evaluating model outputs by comparing them with other models and studies for individual pollutants. This comparison is presented in Supplementary Table 7 . The results show that our model outputs for global inputs of nitrogen, phosphorus, microplastics, triclosan and Cryptosporidium are generally in line with other models and studies. For example, our model quantified 9.5 Tg of nitrogen to rivers from point sources in 2010. Other models quantified 6.4–10.4 Tg of nitrogen to rivers from points sources during 2000–2010 10 , 46 , 69 (Supplementary Table 7 ). For phosphorus, we quantified 1.6 Tg in 2010 whereas the other models quantified 1.0–1.5 Tg for the period of 2000–2010 10 , 46 , 69 . For 2050, we quantified 5.4–21.0 Tg of nitrogen and 0.6–3.5 Tg of phosphorus in 2050 (ranges for the five scenarios). van Puijenbroek et al. 10 quantified 13.5–17.9 Tg of nitrogen and 1.6–2.4 Tg of phosphorus in 2050 under the five SSPs. For Cryptosporidium , our model quantified 1.6 × 10 9 oocysts in 2010 which is 1.1–1.4 × 10 9 oocysts in another model in 2000–2010 11 , 23 (Supplementary Table 7 ). For 2050, our model quantified 0.4–2.9 × 10 9 oocysts (range for the five scenarios). For the Low urb -Low wwt scenario, this value is 2.44 × 10 9 oocysts, which is comparable with 2.28 × 10 9 oocysts from the other model 11 , 23 . To our knowledge, van Wijnen, et al. 20 is the only study quantifying triclosan export by rivers. Our estimates for Danube, Zhujiang and Ganges are comparable with estimates of van Wijnen et al. 20 (Supplementary Table 7 ). For microplastics, our model quantified 0.45 Tg entering rivers globally in 2010. Best 9 indicated loads of 0.41–4.00 Tg of plastics in 32 world’s rivers. This is higher than our estimate because Best 9 accounts for macro- and microplastics whereas we only consider microplastics. Avio et al. 13 indicated 0.27 Tg of plastics to oceans in some regions in the world. This is lower than our estimate because we quantify inputs of plastics to rivers and not to the oceans. The other reasons for the differences between our model and other studies are in data inputs and the spatial level of detail. We focus on sub-basin analyses with the consistent model inputs for multiple pollutants (Supplementary Table 7 , Supplementary Figs. 1 – 13 ).

Approach 2: evaluating model outputs by comparing the spatial variability in pollution hotspots with other studies. We reviewed the literature on pollution hotspots in the world for individual pollutants 8 , 9 , 10 , 11 , 12 , 16 , 55 , 56 , 70 . Our pollution hotspots for multiple pollutants are in line with the existing studies for individual pollutants. For example, most pollution often happens in densely populated and highly urbanized areas 8 , 9 , 10 , 11 , 12 , 16 , 55 , 56 . For example, Best 9 indicated over 80% of large transboundary rivers in the world with multiple pollutants. For many large cities in polluted regions, the demand for water already exceeds its availability. For example, water scarcity (ratio between the water demand and availability) has been already reported for cities in countries such as China (e.g., Shanghai, Beijing), India (e.g., Delhi, Kolkata, Bangalore, Hyderabad), Mexico, North America (e.g., Los Angeles) 70 . In the future, river pollution will further decrease the availability of clean water in many urban regions 4 , 7 , 8 , 71 . We show that it is technically possible to increase the availability of clean water with implementing advanced technologies (High urb _High wwt , Figs. 3 – 6 ). However, future analyses for multi-pollutant hotspots are lacking in the existing literature. A few global models performed future analysis for individual pollutants 10 , 11 , 18 , 20 where urbanization was taken into account by 2050. Their results indicate pollution hotspots where human activities are most intensive, which is in line with our study. However, studies exploring trends in multi-pollutant hotspots by 2100 do not exist. We explore trends in pollution hotspots for multi-pollutant problems covering the entire 21st century under the five scenarios with different socio-economic developments and levels of wastewater treatment.

Approach 3: evaluating model outputs for pollution hotspots by sensitivity analysis. In Fig. 5 , we showed multi-pollutant hotspots. These hotspots were defined as at least a 30% increase in inputs of more than one pollutant to rivers during 2010–2050, 2010–2100 and 2050–2100. This definition is modest and easier to understand and interpret. We checked if the pollution hotspots remain the same by changing a 30% increase to 10% (Supplementary Figs. 18 – 19 ) and 50% (Supplementary Fig. 20 – 21 ). Results of this sensitivity analysis indicate that our main messages stay the same: Africa will become a hotspot region with multiple pollutants in rivers in the 21st century and advanced technologies may help to reduce pollution in many rivers of the world.

Approach 4: evaluating model inputs by a sensitivity analysis. We performed a comprehensive sensitivity analysis for all important model inputs underlying the calculations. In total, there are 25 model input parameters included in this analysis. Every model input was changed by +10% and −10%. As a result, we did 50 runs of the model for the year 2010. We analyzed the results of the 50 runs for 10,226 sub-basins and five pollutants: Cryptosporidium , nitrogen, phosphorus, triclosan and microplastics. Details can be found in Supplementary Tables 9 – 12 and Supplementary Fig. 17 .

In general, increasing the model inputs (13 out of 25) that are responsible for excretion or consumption rates of pollutants in urban waste lead to more pollutants in rivers (Supplementary Tables 10 – 12 ). The opposite is observed when these model inputs are decreased. An exception is HDI for Cryptosporidium and microplastics. Model inputs that are responsible for wastewater treatments (6 out of 25) have the following effect on the model outputs: increases in these inputs lead to less pollutants in rivers and vice versa. Model inputs (6 out of 25) that are responsible for the number of people (urban and rural) connected to sewage systems have the following effect on the model outputs: increases in these inputs lead to more pollutants in rivers and vice versa (Supplementary Tables 10 – 12 ).

We find that model outputs are most sensitive to changes in 2–5 out of the 25 model inputs. The sensitivities vary among sub-basins and pollutants. These model inputs are HDI (sensitive for Cryptosporidium and microplastics), the fractions of secondary (sensitive for triclosan and microplastics) and tertiary (sensitive for all five pollutants) treatment, and the removal efficiencies of secondary (sensitive for triclosan and microplastics) and tertiary (sensitive for all five pollutants) treatment. We analyze model outputs for 10,226 sub-basins that are sensitive to changes in those 2–5 model inputs. Supplementary Tables 11 – 12 show the percentages of the sub-basin areas where model outputs for the five pollutants change by: <5%, 5–10%, 10–50% and >50%. Supplementary Fig. 17 shows the location of the sub-basins for which model outputs are sensitive to one or more model inputs.

The model results for sub-basins covering over two-thirds of the global surface area changed by less than 5% (Supplementary Tables 11 – 12 ). For ≤13% of the global surface area the model outputs changed between 5–10%. This is for all pollutants. For ≤8% of the global area, the changes are between 10–50% in the model outputs. Exceptions are Cryptosporidium and microplastics, which are relatively sensitive for HDI. In one-third of the sub-basin area the model output for Cryptosporidium changed 10–50% as a result of changes in HDI. For microplastic, the changes may be even higher. However, the number of basins with changes above 50% is small. These results show that HDI is an important model input for Cryptosporidium and microplastics (see Supplementary Tables 1 , 9 – 12 ).

Approach 5: evaluating model inputs by comparing them with independent datasets. We provide this comparison in Supplementary Table 8 , Supplementary Figs. 15 and 16 . Comparison results build trust in our model inputs. We compared the following important model inputs for 2010 and 2050 scenarios: total population, population with sewer connections, distribution of treatment types, removal efficiencies of pollutants, nutrients in human excretion (Supplementary Table 8 ). We compared these inputs with van Puijenbroek et al. 10 who recently published global analyses of nutrient inputs to rivers from point sources. We also compared our population from Jones and O’Neill 53 with another global dataset from Kc and Lutz 34 (Supplementary Fig. 16 ). Our model inputs are well compared with the mentioned studies. Furthermore, we compared our HDI index for 2010 and 2050 with the HDI index from Crespo Cuaresma and Lutz 57 (Supplementary Fig. 15 ). HDI is an important input in our model to quantify the excretion of Cryptosporidium . HDI influences the treatment developments and consumption of microplastics associated with the use of car tyres. Our values for HDI under the five scenarios are well compared with the values of Crespo Cuaresma and Lutz 57 ( R 2  > 0.88 for the five scenarios).

Results of these five approaches give us trust in using our multi-pollutant model to explore future trends in inputs of multiple pollutants to rivers from urbanization activities. All data are available in Strokal et al. 72 and Strokal et al. 73 .

Reporting summary

Further information on research design is available in the Nature Research Reporting Summary linked to this article.

Data availability

All the datasets generated and analysed during this study are publicly available in the Data Archiving and Networked Services (DANS Easy) repository: https://doi.org/10.17026/dans-zyx-jce3 73 . The data will be available for download from 01–04–2021. The data supporting the findings of this study are described in the following metadata record: https://doi.org/10.6084/m9.figshare.13333796 72 .

Code availability

All equations to the model are provided in the supplementary information files of this study and in the Data Archiving and Networked Services (DANS Easy) repository: https://doi.org/10.17026/dans-zyx-jce3 . The data will be available for download from 01–04–2021.

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Acknowledgements

M.S. (the corresponding author) was financially supported by a Veni-grant (0.16.Veni.198.001) and a KNAW-MOST SURE + project (5160957392).

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M.S. led this manuscript. M.S. was responsible for designing the manuscript, developing a multi-pollutant model, and analyzing and writing the manuscript. C.K. substantially assisted in designing the manuscript, developing the model and analyzing the results. Z.B., W.F., N.H., A.A.K., L.V., M.T.H.V., J.E.S. and J.W., contributed largely in developing the global multi-pollutant model that was used in the manuscript for future analyses of the impact of urbanization on river pollution. They and other authors provided information to the manuscript and advised on the analyses. All authors assisted the interpretations of the Shared Socio-economic Pathways. These pathways are used in the manuscript for multiple pollutants. All authors read and commented on the text. All authors approved the final version and were involved in the accountability for all aspects of the manuscript.

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Strokal, M., Bai, Z., Franssen, W. et al. Urbanization: an increasing source of multiple pollutants to rivers in the 21st century. npj Urban Sustain 1 , 24 (2021). https://doi.org/10.1038/s42949-021-00026-w

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“Unsecured guns lead to preventable tragedies, and by incentivizing the use of gun safes, the SAFES Act will help protect our communities. Each step we take in Congress to mitigate these incidents is critical, and I’m proud to support this common sense life-saving legislation.”

Representative Mikie Sherrill (NJ-11) said: 

“Far too many gun deaths – especially involving children – are the result of firearms that are not stored safely. I am proud to expand our efforts to ensure that Americans have access to secure storage information and financial assistance to purchase safe storage devices by helping to lead the Securing All Firearms Effectively and Safely Act. This commonsense legislation will make secure storage more affordable for families and is a step in the right direction as we work to end the American gun violence epidemic once and for all. As a former expert shot in the U.S. Navy, I know that it is absolutely critical that firearms are stored properly – locked, away from ammunition, and out of the reach of untrained users.”

The SAFES Act is endorsed by Brady United Against Gun Violence, GIFFORDS, and March for Our Lives. 

Mark Collins, Director of Federal Policy for Brady said: 

“Each day in the United States, eight children are shot as a result of improperly secured firearms. Storing firearms securely, locked, unloaded, and away from ammunition is essential to protecting ourselves and our loved ones from accidental shootings and unauthorized access. The Securing All Firearms Effectively and Safely (SAFES) Act will incentivize safe firearm storage and lessen the potential financial barrier to purchasing a gun safe. Brady applauds Congresswoman Nikema Williams for introducing the SAFES Act and for her commitment to promoting safe firearm storage.” 

Emma Brown, Executive Director of GIFFORDS said: 

“When guns are stored safely, we see a dramatic decrease in suicide and unintentional injury, especially among children and teens. Rep. Williams’ bill incentivizes the safe and smart choice for gun owners and their families, and encourages safe storage as a standard and affordable practice. Congress should pass this sensible and important bill.”

Click here for the text of the SAFES Act .

Click here for a one pager on the SAFES Act .

Contact: Amber English Coleman, [email protected]  

Congresswoman Nikema Williams proudly serves Georgia’s Fifth Congressional District on the exclusive Financial Services Committee. She is a champion of voting rights and builds on the Fifth District’s legacy as the cradle of the civil rights movement as co-chair of the Congressional Voting Rights Caucus. Congresswoman Williams is committed to closing the racial wealth gap and ensuring the promise of America for all–regardless of your ZIP code or bank account.

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What Is ChatGPT and How Does It Work?

How does chatgpt make money, potential benefits of chatgpt, disadvantages and dangers of chatgpt, inner turmoil, the bottom line.

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What Is ChatGPT, and How Does It Make Money?

The popular chatbot has become a symbol of the promises, perils, and potential profits of artificial intelligence

Getty Images / Laurence Dutton

ChatGPT, the free chatbot released in November 2022 by the artificial intelligence (AI) research company OpenAI, has taken the internet by the proverbial storm. In its first years of existence, ChatGPT has been used to write essays and articles, summarize long texts, explain complicated arguments, write code, translate text, make workout plans, and even create bedtime stories for children.

Some artificial intelligence experts believe that ChatGPT could revolutionize both the way that humans interact with chatbots and AI more broadly. Others have expressed serious concerns about the technology's potential for harm.

Key Takeaways

• ChatGPT is a chatbot released in November 2022 by OpenAI, an artificial intelligence research company.
• Chatbots are AI systems that engage in spoken or written dialogue and are commonly used in the customer service sections of company websites as well as virtual assistants like Siri or Alexa.
• The "GPT" in ChatGPT stands for "Generative Pre-training Transformer," referring to the way it processes language.
• A free version of ChatGPT is available on OpenAI's website, and the company also sells a more advanced version on a subscription basis.
• ChatGPT generates billions in annualized revenues but continues to be loss-making.

ChatGPT is an AI model that engages in conversational dialogue. It is an example of a chatbot , akin to the automated chat services found on some companies' customer service websites.

The technology was developed by OpenAI, a tech research company that has said it is dedicated to ensuring "that artificial general intelligence benefits all of humanity." The "GPT" in ChatGPT stands for "generative pre-training transformer," referring to the way that ChatGPT processes language.

What sets ChatGPT apart from chatbots of the past, is that ChatGPT was trained using reinforcement learning from human feedback (RLHF). RLHF involves the use of human AI trainers and reward models to develop ChatGPT into a bot capable of challenging incorrect assumptions, answering follow-up questions, and admitting mistakes.

GPT stands for "generative pre-training transformer."

To put ChatGPT to the test, Investopedia asked it to "write a journalistic-style article explaining what ChatGPT is." The bot responded that it was "designed to generate human-like text based on a given prompt or conversation." It added that, because it is trained on a data set of human conversations, it can understand context and intent and is able to have more natural, intuitive conversations.

In its response to our prompt, ChatGPT said that its applications could include customer service bots, the creation of content for social media or blogs, and the translation of text from one language to another.

OpenAI launched ChatGPT as a nonprofit in 2015, relying on donations for funding because its founders didn't like the idea of artificial intelligence being used for commercial purposes. Over time, however, the company said "it became increasingly clear that donations alone would not scale with the cost of computational power and talent required to push core research forward, jeopardizing our mission." So, in 2019, it created a for-profit subsidiary overseen by the nonprofit's board of directors.

A lot has changed since then. OpenAI's sales have been rocketing and were reported to have surpassed $2 billion on an annualized basis in December 2023 off the back of the soaring popularity of ChatGPT. This figure is expected to continue soaring in the future as businesses flock to use OpenAI’s technology to adopt generative AI tools in the workplace.

A free version of ChatGPT remains available on OpenAI's website. In addition, the company offers a premium version, ChatGPT Plus, with a subscription price of $20 per month. The free version comes with limited access to data analysis, file uploads, vision, web browsing, custom GPTs, and the latest system: ChatGPT-4.0. And management currently has no plans to make money off non-paying users through selling ads.

In addition, the company sells its application programming interface on a subscription basis to organizations looking to use the model for their own purposes, according to Investopedia's query to ChatGPT itself.

The percentage of Fortune 500 companies rumored to be using OpenAI products.

Despite rising substantially, revenues haven't been enough to cover expenses. ChatGPT continues to be loss-making because of the huge costs associated with building and running its models. And with continued investment needed to develop more sophisticated models in the future, this isn't expected to change anytime soon.

That means the company will continue to need to raise more money. OpenAI's biggest backer Microsoft has pledged up to $13 billion of funding. There have also been stock sales, the most recent of which valued OpenAI at $86 billion.

ChatGPT may be the leader in its field, but it is not without competitors, some with vast resources behind them, including Amazon, Google, and Meta.

While chatbots have existed for some years, ChatGPT is viewed as a significant improvement on the intelligibility, fluidity, and thoroughness of prior models.

As mentioned, ChatGPT has numerous potential uses. They range from relatively direct, chatbot-type functions to much more obscure applications, and it is likely that users will explore a host of other possible ways to utilize this technology in the future. Recent additions include the ability to upload photos for the bot to analyze and real-time language translations.

One demonstration of the sophistication of ChatGPT provided by OpenAI includes a prompt that was designed to trick the bot: asking about when Christopher Columbus (supposedly) came to the United States in 2015. ChatGPT's response easily avoided the trap, clarifying that while Columbus did not come to the U.S. in 2015, it can posit some of the ways he may have reacted to his visit if he had.

OpenAI itself lists some of the limitations of ChatGPT as it currently exists. They include ChatGPT sometimes writing coherent but incorrect statements, making assumptions about ambiguous queries, and tending to be excessively verbose.

In the first weeks of its public release, ChatGPT made headlines for its alleged use among students in creating AI-written papers and other assignments. Concerns about the misuse of ChatGPT for academic cheating grew large enough that a computer science student at Princeton University created an app designed to identify and expose writing created by the bot.

In September 2023, the Authors Guild and more than a dozen prominent fiction writers—including Jonathan Franzen, John Grisham, George R.R. Martin, Jodi Picoult, George Saunders, and Scott Turow—filed a lawsuit charging OpenAI with copyright infringement. It alleged that in order to train ChatGPT, the company had copied the authors' works "wholesale, without permission or consideration." Perhaps more ominously, the suit pointed to the potential for AI to "spit out derivative works," mimicking and competing with the human authors and potentially depriving them of their livelihood.

Several newspapers have also sued OpenAI and Microsoft for copyright infringement.

To some observers, ChatGPT poses additional and potentially even more serious risks. For instance, analysts have predicted that the bot could be used to make malware and phishing attacks more sophisticated, or that hackers may utilize the technology to develop their own AI models that may be less well-controlled. As concerns about misinformation have proliferated, some are especially sensitive to the possibility that ChatGPT could be used to create and share convincing but misleading material of a political nature.

Worse still are concerns that AI might ultimately take on a life of its own, leading even to human extinction—a worry shared by many legitimate scientists and industry experts, not simply a crackpot fringe.

OpenAI's reputation also hasn't been helped by inner turmoil, fueled in part by a clash between non-profit and for profit values.

In a fast-moving chain of events characterized by the New York Times as, "a fight between dueling visions of artificial intelligence," OpenAI's board fired Sam Altman, the company's CEO and its most public face, on Nov. 17, 2023, only to restore him to the position less than a week later.

"Mr. Altman's departure follows a deliberative review process by the board, which concluded that he was not consistently candid in his communications with the board, hindering its ability to exercise its responsibilities," the company said in a statement on Nov. 17. "The board no longer has confidence in his ability to continue leading OpenAI."

Within a matter of hours, Altman appeared to have been hired by Microsoft, a major investor in OpenAI, and virtually the entire staff of OpenAI threatened to resign unless he was rehired. The board relented on Nov. 22, and all but one of its members left the nonprofit. Altman was officially reinstated as OpenAI's CEO a week later.

The upshot of the turmoil, according to many industry commentators, was that the subsidiary's profit motive had won out over the nonprofit board's high-minded mission of serving "all of humanity."

What Makes ChatGPT Stand Out?

ChatGPT's functionality, including its ability to understand context and detail and to recognize when it has made mistakes, is seen as standing out among rivals.

What Is a Large Language Model (LLM)?

A large language model (LLM) is a way of training artificial intelligence tools like ChatGPT. Google, which is deeply involved in the development of AI, defines it as "a statistical language model, trained on a massive amount of data, that can be used to generate and translate text and other content, and perform other natural language processing (NLP) tasks."

What Is ChatGPT Used For?

ChatGPT is primarily used for natural language understanding and generation, making it valuable for tasks like content creation, chatbot development, language translation, and more. It can be used for a variety of tasks, and largely depends on how each user chooses to use it.

ChatGPT is the leading chatbot technology available today. But, not surprisingly, given all of the money likely to be made from artificial intelligence, numerous competitors have developed alternatives to challenge its dominance.

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CNET. " You'll Be Seeing ChatGPT's Influence Everywhere This Year ."

OpenAI. " Introducing ChatGPT ."

OpenAI. " About OpenAI Page ."

Lance B. Eliot, via SSRN. " Generative Pre-Trained Transformers (GPT-3) Pertain to AI in the Law ."

OpenAI. " Our Structure ."

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OpenAI. " ChatGPT ."

Reuters. " OpenAI Unveils New AI Model as Competition Heats Up ."

Bloomberg. " OpenAI Deal Lets Employees Sell Shares at $86 Billion Valuation ."

Northwest.Education. " Top 6 Competitors of ChatGPT ."

The New York Times. " The New ChatGPT Offers a Lesson in A.I. Hype ."

NPR. " A New AI Chatbot Might Do Your Homework for You. But It's Still Not an A+ Student ."

NPR. " A College Student Created an App That Can Tell Whether AI Wrote an Essay ."

The Authors Guild. " Case 1:23-cv-08292 Document 1 ," Page 2.

AP. " Eight US Newspapers Sue ChatGPT-Maker OpenAI and Microsoft for Copyright Infringement ."

Bloomberg. " Viral ChatGPT Spurs Concerns About Propaganda and Hacking Risks ."

Time. " An AI Pause Is Humanity's Best Bet for Preventing Extinction ."

The New York Times. " A.I. Belongs to the Capitalists Now ."

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A comparative study of the influence of communication on the adoption of digital agriculture in the united states and brazil  †.

1. Introduction

2. materials and methods, 2.1. study region, 2.2. survey instrument, 2.3. data collection, 2.4. data analysis.

• n = number of elements in the sample;
• p = probability of finding the phenomenon studied in the population;
• q = probability of not finding the phenomenon studied in the population; and
• E = margin of error.

2.5. Sample Characteristics

3. results and discussion, 3.1. technology adoption, decisions, and benefits, 3.2. level of influence from mass media, social media, and interpersonal meetings, 3.3. relationship between the adoption of technologies and communication channels, 4. conclusions, author contributions, institutional review board statement, data availability statement, acknowledgments, conflicts of interest.

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Colussi, J.; Sonka, S.; Schnitkey, G.D.; Morgan, E.L.; Padula, A.D. A Comparative Study of the Influence of Communication on the Adoption of Digital Agriculture in the United States and Brazil. Agriculture 2024 , 14 , 1027. https://doi.org/10.3390/agriculture14071027

Colussi J, Sonka S, Schnitkey GD, Morgan EL, Padula AD. A Comparative Study of the Influence of Communication on the Adoption of Digital Agriculture in the United States and Brazil. Agriculture . 2024; 14(7):1027. https://doi.org/10.3390/agriculture14071027

Colussi, Joana, Steve Sonka, Gary D. Schnitkey, Eric L. Morgan, and Antônio D. Padula. 2024. "A Comparative Study of the Influence of Communication on the Adoption of Digital Agriculture in the United States and Brazil" Agriculture 14, no. 7: 1027. https://doi.org/10.3390/agriculture14071027

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Probllama: Ollama Remote Code Execution Vulnerability (CVE-2024-37032) – Overview and Mitigations

Wiz Research discovered CVE-2024-37032, an easy-to-exploit Remote Code Execution vulnerability in the open-source AI Infrastructure project Ollama.

Introduction & Overview 

Ollama is one of the most popular open-source projects for running AI Models, with over 70k stars on GitHub and hundreds of thousands of monthly pulls on Docker Hub . Inspired by Docker, Ollama aims to simplify the process of packaging and deploying AI models. 

Wiz Research discovered an easy-to-exploit Remote Code Execution vulnerability in Ollama: CVE-2024-37032, dubbed “Probllama.” This security issue was responsibly disclosed to Ollama’s maintainers and has since been mitigated. Ollama users are encouraged to upgrade their Ollama installation to version 0.1.34 or newer. 

Our research indicates that, as of June 10, there are a large number of Ollama instances running a vulnerable version that are exposed to the internet. In this blog post, we will detail what we found and how we found it, as well as mitigation techniques and preventative measures organizations can take moving forward.  

AI Security Takeaways 

Taken as a whole – and in light of the Wiz Research team’s ongoing focus on the risk inherent to AI systems – our findings underscore the fact that AI security measure s have been largely sidelined in favor of focusing on the transformative power of this technology, and its potential to revolutionize the way business gets done.  

Organizations are rapidly adopting a variety of new AI tools and infrastructure in an attempt to hone their competitive edge. These tools are often at an early stage of development and lack standardized security features, such as authentication. Additionally, due to their young code base, it is relatively easier to find critical software vulnerabilities, making them perfect targets for potential threat actors. This is a recurring theme in our discoveries – see prior Wiz Research work on AI-as-a-service-providers Hugging Face and Replicate , as well as our State of AI in the Cloud report and last year’s discovery of 38TB of data that was accidentally leaked by AI researchers.  

Over the past year, multiple remote code execution (RCE) vulnerabilities were identified in inference servers, including TorchServe, Ray Anyscale, and Ollama. These vulnerabilities could allow attackers to take over self-hosted AI inference servers, steal or modify AI models, and compromise AI applications.  

The critical issue is not just the vulnerabilities themselves but the inherent lack of authentication support in these new tools. If exposed to the internet, any attacker can connect to them, steal or modify the AI models, or even execute remote code as a built-in feature (as seen with TorchServe and Ray Anyscale ). The lack of authentication support means these tools should never be exposed externally without protective middleware, such as a reverse proxy with authentication. Despite this, when scanning the internet for exposed Ollama servers, our scan revealed over 1,000 exposed instances hosting numerous AI models, including private models not listed in the Ollama public repository, highlighting a significant security gap. 

CROC Talks: RCE Vulnerability in Ollama explained

RCE Vulnerability in Ollama explained

Mitigation & detection 

To exploit this vulnerability, an attacker must send specially crafted HTTP requests to the Ollama API server. In the default Linux installation , the API server binds to localhost, which reduces remote exploitation risk significantly. However, in docker deployments ( ollama/ollama ), the API server is publicly exposed , and therefore could be exploited remotely. 

Wiz customers can use the pre-built query and advisory in the Wiz Threat Center to search for vulnerable instances in their environment. 

Explanation and Technical Description 

Why research ollama .

Our research team makes an active effort to contribute to the security of AI services, tooling, and infrastructure, and we also use AI in our research work. 

For a different project, we looked to leverage a large-context AI model. Luckily, around that time, Gradient released their Llama3 version which has a context of 1m tokens .  

Being one of the most popular open-source projects for running AI Models with over 70k stars on GitHub and hundreds of thousands of monthly pulls on Docker Hub , Ollama seemed to be the simplest way to self-host that model 😊. 

 Ollama Architecture 

Ollama consists of two main components: a client and a server. The server exposes multiple APIs to perform core functions, such as pulling a model from the registry, generating a prediction for a given prompt, etc. The client is what the user interacts with (i.e. the front-end), which could be, for example, a CLI (command-line interface). 

While experimenting with Ollama, our team found a critical security vulnerability in an Ollama server. Due to insufficient input validation, it is possible to exploit a Path Traversal vulnerability to arbitrarily overwrite files on the server. This can be further exploited into a full Remote Code Execution as we demonstrate below. 

This issue is extremely severe in Docker installations, as the server runs with root privileges and listens on 0.0.0.0 by default – which enables remote exploitation of this vulnerability. 

It is important to mention that Ollama does not support authentication out-of-the-box. It is generally recommended to deploy Ollama behind a reverse-proxy to enforce authentication, if the user decides to expose its installation. In practice, our research indicates that there are a large number of installations exposed to the internet without any sort of authentication. 

The Vulnerability: Arbitrary File Write via Path Traversal 

Ollama’s HTTP server exposes multiple API endpoints that perform various actions.  

One of the endpoints, /api/pull , can be used to download a model from an Ollama registry. 

By default, models are downloaded from Ollama’s official registry ( registry.ollama.com ), however, it is also possible to fetch models from private registries.

While Ollama's official registry can be considered "trusted," anyone can set up their own registry and host models on it. As researchers, we were interested in this attack surface – are private registries being blindly trusted? What damage could a malicious private registry cause? 

What we found is that when pulling a model from a private registry (by querying the http://[victim]:11434/api/pull API endpoint), it is possible to supply a malicious manifest file that contains a path traversal payload in the digest field. 

The digest field of a given layer should be equal to the hash of the layer. Among other things, the digest of the layer is also used to store the model file on the disk:  

/root/.ollama/models/blobs/sha256-04778965089b91318ad61d0995b7e44fad4b9a9f4e049d7be90932bf8812e828

However, we found that the digest field was used without proper validation, resulting in path traversal when attempting to store it on the filesystem. This issue can be exploited to corrupt arbitrary files on the system. 

Achieving Arbitrary File Read 

By exploiting the previous issue, we can plant an additional malicious manifest file on the server (e.g /root/.ollama/models/manifests/%ATTACKER_IP%/library/manifest/latest ), which effectively registers a new model to the server. We found out that if our model’s manifest contains a traversal payload for the digest of one of its layers, when attempting to push this model to a remote registry via the http://[victim]:11434/api/push endpoint, the server will leak the content of the file specified in the digest field. 

Finally, Remote Code Execution 

As we mentioned previously, it is possible to exploit the Arbitrary File Write vulnerability to corrupt certain files in the system. In Docker installations, it is pretty straightforward to exploit it and achieve Remote Code Execution , as the server runs with root privileges. 

The simplest way we thought of achieving remote-code-execution would be to corrupt ld.so configuration files, specifically /etc/ld.so.preload . This file contains a whitespace - separated list of shared libraries that should be loaded whenever a new process starts. Using our Arbitrary File Write exploit-primitive, we plant our payload as a shared library on the filesystem ( /root/bad.so ) and then we corrupt etc/ld.so.preload to include it. Finally, we query the /api/chat endpoint on the Ollama API Server, which subsequently creates a new process and thus loads our payload! 

Regarding exploitation of instances which do not run with root privileges - we do have a strategy for exploitation that leverages our /Arbitrary File Read primitive. However, it will be left as an exercise for the reader 😊 

Conclusions 

 CVE-2024-37032 is an easy-to-exploit remote code execution that affects modern AI infrastructure. Despite the codebase being relatively new and written in modern programming languages, classic vulnerabilities such as Path Traversal remain an issue. 

Security teams should update their Ollama instances to the latest version to mitigate this vulnerability. Furthermore, it is recommended not to expose Ollama to the internet unless it is protected by some sort of authentication mechanism, such a reverse-proxy. 

Responsible disclosure timeline 

We responsibly disclosed this vulnerability to Ollama’s development team in May 2024. Ollama promptly investigated and addressed the issue while keeping us updated. 

May 5, 2024 – Wiz Research reported the issue to Ollama.

May 5, 2024 – Ollama acknowledged the receipt of the report. 

May 5, 2024 – Ollama notified Wiz Research that they committed a fix to GitHub. 

May 8, 2024 – Ollama released a patched version. 

June 24, 2024 – Wiz Research published a blog about the issue. 

Ollama committed a fix in about 4 hours after receiving our initial report, demonstrating an impressive response time and commitment to their product security. 

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