How to Write a Dissertation Literature Review

A dissertation literature review is a critical synthesis of the published research on your topic. It explains what is already known, groups studies by theme or debate, evaluates their strengths and weaknesses, and ends by identifying the gap your own research addresses. It is not a list of summaries; markers reward comparison, evaluation and a clear line of argument.

Below is a practical method that works for undergraduate and master's dissertations in the UK: how to search, how to organise sources in a synthesis matrix, how to structure the chapter and how to write critically. If you would like an expert to review your chapter plan or draft, get dissertation literature review help from a tutor who specialises in your field.

What is a literature review in a dissertation?

A literature review is the chapter of a dissertation that surveys and critically analyses existing scholarship relevant to your research question. It establishes the theoretical background, shows the main debates and methods in the field, and justifies your study by identifying an unanswered question, a contradiction or a limitation in the current evidence.

It has four jobs:

1. Context: show what is known and how the field developed.
2. Critique: evaluate the quality and limits of key studies.
3. Connection: group and compare studies to reveal patterns and disagreements.
4. Justification: lead logically to your research gap and question.

How long should a dissertation literature review be?

A literature review usually takes 20 to 30% of a dissertation's word count. That is roughly 2,000 to 3,000 words in a 10,000-word undergraduate dissertation and 3,000 to 4,500 words in a 15,000-word master's dissertation. A dissertation based entirely on secondary research may give it a larger share. Your handbook may set a specific expectation.

Step 1: How do you search for literature?

Start with your module reading list and a few key recent review articles, then search your library's databases (such as Scopus, Web of Science, PubMed, JSTOR or discipline-specific databases) and Google Scholar. Use Boolean operators to combine concepts, and follow the reference lists of the strongest papers to find foundational work.

A simple search plan:

• Concepts: break your question into two or three key concepts.
• Synonyms: list alternative terms for each, for example "remote work" OR "telework" OR "hybrid working".
• Combine: use AND between concepts and OR within them.
• Limit: set date ranges, language and peer-reviewed filters that fit your topic.
• Record: keep a log of databases, search strings and dates, which helps you write the methodology later.

Step 2: How do you organise sources with a synthesis matrix?

A synthesis matrix is a table that records each source against the themes of your review, so you can see where studies agree, conflict or leave gaps. It turns a pile of notes into the structure of your chapter, because each column becomes a section and each row shows how a source contributes.

This is an illustrative matrix with placeholder studies. Read down a column and you have a paragraph: findings on productivity are mixed, apparently depending on experience and management, which is a gap your study might address.

Step 3: How do you structure a literature review?

Most strong dissertation literature reviews are structured thematically, with a short introduction, three to five sections each built around a theme or debate, and a conclusion that states the research gap. Chronological structure suits topics where the history of thinking matters, and methodological structure suits fields where how studies were done explains why their findings differ.

A reliable outline for a thematic review:

1. Introduction: scope, how sources were selected and the order of themes.
2. Theme 1: the foundational debate or concept.
3. Theme 2: the main body of empirical evidence.
4. Theme 3: the area of disagreement or limitation closest to your question.
5. Conclusion: summary of what is known and the precise gap, leading to your research question.

Step 4: How do you write critically, not descriptively?

To write critically, compare and evaluate sources instead of summarising them one at a time. Group studies that share a finding, explain why others disagree (method, sample, context or date), judge the strength of the evidence and say what it means for your question. Every paragraph should make a point about the literature, supported by several sources.

Descriptive (scores lower): Smith (2021) studied remote workers and found productivity increased. Jones (2022) interviewed managers and found problems with communication. Patel (2023) found that experience mattered.

Critical (scores higher): Evidence on remote-work productivity is mixed and appears to depend on employee experience. Large surveys report gains (Smith, 2021), but they rely on self-reported output, whereas firm-level data shows improvement only among experienced staff (Patel, 2023). Interview evidence of communication problems (Jones, 2022) may explain this gap, though its small sample limits how far it generalises.

The sources in these two examples are placeholders that show the technique. The critical version makes a claim, groups the evidence, explains the disagreement and evaluates quality.

Useful phrases for critical writing:

• "In contrast to…, X argues that…"
• "These findings should be treated with caution because…"
• "A limitation shared by these studies is…"
• "Taken together, the evidence suggests…, although…"

Step 5: How do you identify the research gap?

The research gap is what the literature has not yet answered convincingly. It might be an under-studied population or context, conflicting findings, an outdated evidence base, a methodological weakness or a theory that has not been tested in practice. State it precisely in the conclusion of the review and link it directly to your research question.

What is the difference between a literature review and a systematic review?

A dissertation literature review selects and critically discusses the most relevant studies to frame your research. A systematic review follows a pre-defined, reproducible protocol to find, screen and appraise all eligible studies on a question, often reported using the PRISMA framework. Some health and social science dissertations are systematic reviews in their own right.

Common literature review mistakes

• Summarising one source per paragraph with no comparison.
• Including sources because they are on the topic, not because they serve the argument.
• Relying on old or non-academic sources when recent peer-reviewed work exists.
• Ignoring studies that disagree with your expected finding.
• Ending without stating a clear research gap.
• Quoting heavily instead of paraphrasing and analysing.

When to get help with a literature review

If you have read widely but cannot see the themes, or your supervisor says your review is too descriptive, a specialist can help you build a synthesis matrix, restructure the chapter and sharpen the critical analysis. FLN Tutors' dissertation help covers literature reviews, methodology and every other chapter, with feedback from tutors in your discipline. For final polishing, see proofreading and editing.

We provide guidance and feedback on your own work in line with your university's rules and our academic integrity policy.

FAQs

How many sources should a dissertation literature review have?

There is no fixed number, but undergraduate literature reviews commonly draw on 20 to 40 sources and master's reviews on 40 to 80, depending on the field and topic. What matters is that the key studies are covered, the sources are credible and recent where appropriate, and each one contributes to the argument.

Can a literature review be written in first person?

Most literature reviews use an impersonal academic style, but a brief first-person statement of scope ("this review focuses on…" or "I focus on…") is accepted in many disciplines. Follow your department's style guidance and your supervisor's preference.

Should a literature review have headings?

Yes, in most dissertations. Headings for each theme help the reader follow your structure and help you keep each section focused. Use descriptive headings that state the theme, such as "Productivity Outcomes of Remote Work", rather than generic labels.

How old can sources be in a literature review?

Prioritise research from roughly the last five to ten years for current evidence, but include older foundational or seminal works that defined the field. In fast-moving fields such as technology or medicine, recent sources matter more; in history or philosophy, older sources may be central.

What is a synthesis in a literature review?

Synthesis is combining several sources to make a point that no single source makes alone, for example, showing that three studies agree on one finding but differ on another because of their methods. It is the opposite of summarising sources one by one and is what markers most often look for.

Do I need a theoretical framework in my literature review?

Many dissertations include the theoretical framework within or straight after the literature review, explaining the theory or model that shapes your research question and analysis. Some departments ask for a separate chapter. Check your handbook, and ask your supervisor if the requirements are unclear.

How do I start writing a literature review?

Start with your synthesis matrix rather than a blank page. Pick the theme you understand best, write a paragraph that makes one claim supported by several sources, and build from there. Write the introduction and conclusion of the chapter last, once the themes and gap are clear.

What is the difference between a literature review and an annotated bibliography?

An annotated bibliography lists sources with a short summary and evaluation of each, one at a time. A literature review integrates sources into a structured argument organised by theme. Annotated bibliographies are a useful early step, but a literature review must synthesise.

How do you end a literature review?

End with a short conclusion that summarises the main findings across your themes, states clearly what remains unknown or contested, and explains how your research question responds to that gap. This conclusion is the bridge into your methodology chapter.