How to write a research paper introduction (and a thesis chapter 1)

What should the introduction of a research paper include?

Four things, and not much else. The broad area and why it matters. What earlier studies have established, cited properly. What those studies leave open. And what your paper does, stated as an aim, a question or a hypothesis.

Our guide on how to write a research paper describes this as a funnel and gives typical word counts for each IMRaD section. Here we go one level down: which sentence does which job.

Leave out the full methods, the results and a history of the field. If your journal wants a separate literature review or theory section (common in management and education), the introduction gets shorter. It still can’t skip the gap.

What is the CARS model for research introductions?

John Swales, an applied linguist at the University of Michigan, studied how published article introductions are actually built. In Genre Analysis: English in Academic and Research Settings (Cambridge University Press, 1990) he described them as three “moves”, each made of smaller “steps”. He named the pattern CARS: Create a Research Space.

The steps in Move 1 are options, not a checklist.

Move 2 is where the argument lives. Swales’s four options are worth knowing because “indicating a gap” is not the only one, and it is the weakest when the gap is just “nobody has studied this in Tamil Nadu”. Counter-claiming (earlier work is wrong or incomplete in a specific way) and question-raising (the evidence leaves a question open) are often stronger. How to build that sentence properly is covered in our guide to writing a research gap statement, so I won’t repeat it here.

Move 3 varies most from journal to journal. Some journals’ introductions end with a sentence announcing the main finding; others never do. Some outline the article section by section; short papers usually don’t. Read three recent introductions in your target journal and copy their habits.

Swales revisited the model in Research Genres (2004), and his later textbook with Christine Feak (Academic Writing for Graduate Students, 3rd edition, 2012, the version the USC Libraries writing guide follows) calls the first step “claiming importance”. Same logic, slightly different labels.

Use CARS to check a draft. Written step by step from the labels, an introduction reads stiffly, and reviewers can tell.

Research paper introduction example, annotated

The topic is made up. Square brackets mark where a real introduction would need a citation; don’t quote any claim here as fact.

Paragraph 1

Cyclone early-warning systems on India’s east coast are widely credited with reducing deaths in severe storms [cite disaster management reports]. Alerts that once travelled by siren, radio and village volunteers now also reach households as SMS and voice messages in the local language [cite]. Research on these alerts has concentrated on delivery: how many phones received the message, and how quickly [cite; cite].

What it does: Move 1. Claim importance with evidence, generalise, then review what earlier research measured. Nothing about “the importance of disaster management for the nation”.

Paragraph 2

Receiving a warning is not the same as acting on it. Studies of evacuation decisions show that people weigh a warning against their own experience of past storms, the advice of neighbours and what they stand to lose by leaving [cite; cite]. For fishing households the loss is concrete and immediate: a day at sea, and sometimes the boat and nets left on the shore.

What it does: still Move 1, narrowing. A second body of research, so the gap sits between two things the reader already accepts.

Paragraph 3

Yet studies of SMS alerts have rarely followed the message past delivery in fishing communities, where the decision is usually whether to go to sea at all rather than whether to evacuate. The few that ask about response rely on recall surveys conducted months after the event [cite], which cannot show which part of a message people trusted and which they ignored.

What it does: Move 2. “Yet” signals the turn: a gap (response is rarely studied) plus a counter-claim about method. Reviewers read this paragraph twice.

Paragraph 4

This study examines how fishing households in two coastal blocks of Odisha interpreted and acted on SMS alerts during one cyclone season. Using daily diaries kept by households and follow-up interviews, we identify the features of a message that led families to stay ashore. Section 2 describes the study area and methods, Section 3 reports the findings, and Section 4 discusses their implications for how alerts are worded.

What it does: Move 3. The aim is one sentence. The method is a clause, not a page. Drop the structure sentence if your journal’s articles don’t use one.

What are the common mistakes in a research paper introduction?

Roughly in order of how often I see them.

The history-of-the-world opening

“Since ancient times, water has been essential to human civilisation.” “India is an agricultural country.” Every reader already agrees, so the sentence adds little. If your paper is about drip irrigation subsidies in Maharashtra, start with irrigation subsidies.

The gap is buried or missing

Three pages summarising studies one per paragraph, then the gap in half a sentence at the end. If your supervisor asks “so what is new here?”, the introduction hasn’t answered it.

No aim sentence

The introduction ends with “Hence the present study” or with a list of variables, and the reader is left to work out what the paper is trying to find. Write the aim as a full sentence, and word it the same way you word it in the abstract.

Results in the introduction

Coefficients, percentages, a paragraph on what you found: that belongs in the results and the discussion. The exception is the one-sentence principal finding some journals expect in Move 3.

Too long for the paper

An introduction that fills a quarter of the paper usually has a thesis chapter hiding in it. Three to five paragraphs is typical; count them in five recent articles from your target journal.

Before you send the draft to your supervisor, run through this:

• Your first sentence is about your topic, not about India, the world or the history of the discipline.
• A reader can underline the gap sentence. It sits in the second half of the introduction, not on page one of a three-page opening.
• The final paragraph contains one sentence that begins, in effect, “This study…” and says what the study does.
• No numbers from your results appear, unless your field expects a one-line statement of the main finding.

How is the introduction to a literature review or a research proposal different?

A literature review chapter doesn’t need CARS at the start. Its opening states the scope and the order of sections; the argument arrives at the end, with the gap. There is a sample opening and closing in our literature review examples and format guide.

A standalone review article does need a CARS-like introduction, because it has to justify why a review is needed now. For systematic reviews, the PRISMA 2020 checklist asks for two things in the introduction: the rationale for the review in the context of existing knowledge (item 3), and an explicit statement of the objectives or questions it addresses (item 4).

A research proposal has the same three moves, but the Move 1 evidence has to prove a problem exists, not just that a topic is interesting, and Move 3 is written in the future tense. The proposal guide shows how the introduction fits into a two-to-four-page research proposal. In a synopsis for your DC or RAC, the same opening becomes the background and statement of the problem.

How is chapter 1 of a thesis different from a paper introduction?

In scale and in audience. A journal reader decides in two minutes whether to keep reading. An examiner reads chapter 1 slowly, then checks every later chapter against its promises.

So chapter 1 carries parts a paper never has (significance, scope, definitions, a chapter plan and more). Their usual order is set out in our guide to PhD thesis structure, and the hardest of them has its own guide on the statement of the problem.

The CARS moves are still there, just stretched. Background is Move 1. The problem statement and the gap are Move 2. Objectives, scope and the chapter plan are Move 3.

Don’t paste your synopsis in as chapter 1; your study has moved since year one. Keep the core problem, update the evidence and the tense, and revise chapter 1 last. I’ve seen too many theses where chapter 1 lists five objectives and the results chapters answer four.