How to write an essay introduction

Write it last

This is the single most useful piece of advice about introductions and the most consistently ignored. An introduction states what the essay argues, and you do not reliably know that until the essay is written.

Essays change while being drafted. The argument you set out to make is rarely the one that survives contact with the evidence, and an introduction written on day one describes a different essay from the one you submit.

Write a placeholder — one line saying roughly where you think you are going — and get on with the body. Then replace it when the argument is settled. The final version usually takes twenty minutes because everything in it is already decided.

The four moves

In this order, and each doing a specific job. Most introductions that fail have skipped the third.

• Context — why this question matters, in two or three sentences. Not the history of the universe; the specific reason this is worth asking now.
• Definition — the terms that carry weight and could be understood differently. Only those; defining obvious words wastes the reader's attention.
• Position — your answer to the question, stated. This is the thesis statement and it is the sentence the whole essay exists to support.
• Route — how the argument will proceed, in a sentence or two, so the reader knows what to expect.

The thesis statement

A thesis statement is your answer to the question, in one or two sentences, specific enough that someone could disagree with it. If nobody could disagree, it is a description of your topic rather than a position.

'This essay examines the causes of the 2008 financial crisis' announces a topic. 'The 2008 crisis is better explained by the mispricing of risk in securitised products than by regulatory failure, because the same regulatory framework had not produced comparable instability in the preceding decade' is a thesis.

It should also be provable within your word count. A thesis about the whole of a field cannot be supported in 2,000 words, and an over-large claim is the commonest reason an essay reads as thin.

Put it at or near the end of the introduction, where the reader is ready for it.

Openings that waste the paragraph

Four are almost universal in student writing and all four spend the reader's attention without buying anything.

How long

About 10% of the word count. Two hundred words for a 2,000-word essay, five hundred for five thousand. A dissertation introduction is a chapter and follows different rules.

Shorter is usually better than longer. An introduction that runs to 15% has typically started arguing, and an argument in the introduction is a paragraph that belongs in the body.

If you cannot state your position within the first paragraph, the position is probably not settled yet.

Defining terms without padding

Define only terms that carry weight in your argument and could reasonably be understood differently. A definition of a word your marker uses daily is filler.

Where a term is contested, the definition is itself an argument and should be presented as one: say which definition you are adopting, whose it is, and why it suits the question.

Do this in a subordinate clause where possible. 'Taking wellbeing in Ryff's sense of psychological functioning rather than as reported life satisfaction, the evidence...' defines and argues in the same sentence.

Scope and what you are excluding

One sentence saying what the essay does not cover is worth including where the question is broader than the word count. It shows the limitation was a decision rather than an oversight.

Be specific and give a reason: 'The discussion is limited to the UK, where the regulatory framework differs sufficiently from the US that combining them would obscure the mechanism.'

Do not use scope statements to excuse missing analysis a reader would expect. Excluding the central counter-argument because of space is not a scope decision.

The route sentence

One or two sentences telling the reader how the argument proceeds. It is a map, not a table of contents, and it should reflect the logic rather than the section headings.

'The argument proceeds in three steps: first that the standard account misdates the shift, then that the alternative explains the regional variation the standard account cannot, and finally that this changes what the policy response should be' tells a reader what to expect and why.

Avoid 'firstly, secondly, thirdly' as the whole route. Enumeration without connection tells the reader the order and not the logic.

Introductions in longer work

A dissertation introduction chapter is a different document: it establishes the problem, the gap in the literature, the aims and research questions, the significance, and the structure of the thesis, usually across several thousand words.

A report introduction states the decision the report supports and its scope, and the executive summary carries the findings.

A journal article introduction is closest to the essay version but narrower — context, gap, aim, and often a one-sentence statement of what the paper shows.

In every case the same rule holds: write it after you know what the document concludes.

The hook, and whether you need one

Advice written for school essays and for journalism recommends opening with a hook — a striking fact, a question, an anecdote. In academic writing this is optional and frequently counterproductive.

A marker does not need to be enticed into reading; they are going to read it either way. What they need is to know quickly what the essay argues, and a paragraph of scene-setting delays that.

Where an opening fact does work, it is because it is the specific problem the essay addresses rather than an attention-getter. 'Retention gaps between first-generation and continuing-generation students have not narrowed since fees were introduced, despite two decades of widening participation policy' is a first sentence that is doing analytical work.

Rhetorical questions are the weakest version. A question you do not answer immediately postpones your position, and a question you answer in the next sentence would have been better written as the answer.

Checking it at the end

Five checks, each answerable by reading the introduction alone.

• Can a reader state your position after reading it?
• Does the position match what the essay actually argues, after all the drafting?
• Is every defined term one that does work in the argument?
• Have you removed the dawn of time, the dictionary and the fast-paced modern society?
• Does the route sentence describe the logic rather than the headings?