How-to · Step-by-step
How to write an introduction paragraph
An introduction paragraph orients the reader and states the paper’s purpose — moving from a broad opening, through context, to a specific thesis or research question.
The step most authors miss
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Step by step
How to do it
1.Open with a hook
Begin with something that earns the reader’s attention and is relevant to your topic: a striking fact, a pointed question, a brief scenario or a statement of why the issue matters. Avoid clichés such as dictionary definitions or “Since the dawn of time”.
2.Establish the context
Give the background a reader needs to understand the topic — the broader field, key terms, and what is already known. In research writing this is where you summarise relevant prior work and show the conversation your paper joins.
3.Identify the gap or problem
Narrow from the general context to the specific issue your paper addresses. State the problem, the unresolved question, or the gap in existing knowledge — the reason the paper is worth writing. This is the central move of the CARS model.
4.State the thesis or research question
End the introduction with your thesis statement or research question — the specific claim you will argue or the question you will answer. Placing it last gives the paragraph its funnel shape and tells the reader exactly where the paper is heading.
5.Optionally preview the structure
In longer papers, add a sentence outlining how the argument will unfold (“This paper first reviews… then analyses… before concluding…”). This roadmap helps readers follow a complex piece, though it is usually unnecessary in a short essay.
The funnel and the CARS model
A strong introduction narrows like a funnel: wide at the top with general context, tapering to the precise thesis or question at the bottom. In research writing, John Swales’s CARS model — Create A Research Space — describes the same movement more formally through three “moves”: establishing the territory (showing the topic matters and summarising prior work), establishing a niche (identifying a gap, problem or unresolved tension), and occupying the niche (stating your purpose, question or hypothesis and, often, outlining the paper). The funnel for essays and CARS for research papers are the same instinct: bring the reader from the broad field to your specific contribution in a few well-ordered sentences.
Common questions
FAQ
How long should an introduction be?+
It depends on the paper. A short essay often needs a single introductory paragraph; a research article or dissertation may need several paragraphs or a whole section. As a guide, keep it proportionate — long enough to give necessary context and state the thesis, short enough that it does not stray into the detailed argument, which belongs in the body.
Should I write the introduction first or last?+
Many writers draft a working introduction first to fix their direction, then revise it last once the paper is finished and the argument is settled. Because the thesis often sharpens as you write, returning to the introduction at the end ensures it accurately previews what the paper actually argues, rather than what you first intended.
What is the CARS model?+
CARS — Create A Research Space — is John Swales’s three-move template for research introductions: establish the territory by showing the topic matters and reviewing prior work, establish a niche by identifying a gap or problem, then occupy the niche by stating your aim, question or hypothesis. It formalises the broad-to-narrow funnel common to effective introductions.
Going deeper
