How to write a PhD literature review (in nine steps)

For most of my time as a graduate student, I had not idea how to write a PhD literature review.

A PhD literature review is a critical analysis of existing research relevant to your topic. It synthesises what has been studied, identifies gaps in the evidence, and positions your research within the broader academic conversation. A well-written literature review demonstrates scholarly authority and justifies why your research question matters.

In fact, I was scared of the literature review. One day, my supervisor took me to one side and told me that I had no choice: ‘It was going to have to be done before you start fieldwork’.

I was terrified.

Sound familiar? According to Google, 5,000 people a month search for advice on how to write a PhD literature review. And we know from the students who are part of our PhD Writing Community that many struggle with this part of their thesis. If you’re feeling lost, keep reading. In this guide, I’ll walk you through the nine steps involved in conducting and writing a PhD literature review. By the end, if someone ask you ‘how to write a PhD literature review’, you’ll know exactly how to answer.

You’ll realise what I eventually found out: the PhD literature review is easy. Okay, perhaps that’s a bit much. Let me rephrase: Writing a PhD literature review isn’t as hard as you think.

What a PhD literature review isn’t

Let us make one thing very clear. A PhD literature review isn’t just a summary of existing literature. That’s an annotated bibliography and that isn’t what a PhD literature review is about. According to Ridley (2012), this is the mistake most commonly made by doctoral students. Not only will your examiners send this back for corrections, but it may mean the whole PhD thesis is problematic because it isn’t grounded in a critical review of the literature.

What a PhD literature review is

A PhD literature review is a critical assessment of the literature in your field and related to your specific research topic. It plays a crucial role in the wider context of your PhD thesis (this post explains how to structure your PhD thesis, if you need a bit of guidance there too). When discussing each relevant piece of literature, the review must highlight where the gaps are and what the strengths and weaknesses are of particular studies, papers, books, etc. Also, different pieces of literature are compared and contrasted with one another so that themes and relationships are highlighted.

According to Hart (2018), the job of a literature review is to show five things (if you’re using our free PhD Writing Template, you may recognise these):

• What has been written on your topic
• Who the key authors are and what the key works are
• The main theories and hypotheses
• The main themes that exist in the literature
• Gaps and weaknesses that your study will then help fill

Who cares what other people have written and said, or what they haven’t said? Well, you should and your examiners definitely will. For your own study to make sense, it has to be situated in the literature. That means you must relate it to what others are talking about.

If you wanted to build a new mobile phone, you would have to research how other mobile phones are built, find out where they can be improved and then design one that makes those improvements. The literature review is the same.

But where do I start? Here, we list nine steps. Follow each and you’ll be on your way to literature review greatness.

@thephdpeople

If you’re finding your PhD literature review hard, it’s because it is hard. In our writing community, whenever I ask who’s struggling with their lit review, almost every hand goes up—and for good reason. A literature review is a huge, demanding task, and most of us have never had to work at that scale or that level before. Even with excellent supervision, it remains one of the biggest hurdles in the PhD journey. And if your support is limited or inconsistent, it can feel even heavier. So if you’re in the middle of wrestling with your lit review and wondering whether you’re the problem, please don’t. There’s nothing wrong with you, and it has nothing to do with being “smart enough.” It’s hard because it’s hard. Keep going—you’re not alone. #PhDLife #AcademicTikTok #GradSchoolStruggles #PhDStudent #ResearchLife #PhDsupport #BurnoutRecovery #StudyTok #MentalHealthInAcademia #PhDMotivation #PhD #PhDthesis #AcademicChatter #PhDchat

♬ original sound – Dr. Max – Dr. Max

Mapping Your Literature Review

Understanding what goes where in your literature review, and how it all fits together, is tough. That’s why we’ve created a free Literature Review Template & Cheat Sheet. It’s yours for free, and comes with a 10-part guide to structuring every chapter of your thesis. Check it out here.

Step One: Pick a Broad Topic

You will be reviewing literature on a particular topic, so knowing what your topic is beforehand means you can narrow down your search. At this stage your topic is broad. You won’t be able to know the specifics until you do the review itself. For my PhD, which looked at the contributions that local government made to climate change policy, my literature review started with a broad topic of ‘climate change policy’. I didn’t focus in on local government until I had read the literature on climate change policy and realized there was a gap.

So, having a clearly defined purpose is really important. Otherwise you are searching blind. If you refer to your PhD Writing Template, take a look at the box titled ‘Aims & Objectives’ – you’ll need to make sure you have established your aims, scope and research questions.

Step Two: Find the Way In

If you search for your broad topic in Google Scholar, you’ll be presented with millions of results. With my own PhD, a search for ‘climate change policy’ bought up over 3 million results. Obviously it’s unfeasible to read through all these.

So where do you start? Easy: choose the biggest names in your field.

There are three ways to find these:

• Textbooks
• Review articles
• Most-cited articles

Read through these seminal texts and you’ll begin to get an idea of the broad topic.

Step Three: Who’s Saying What & When

Your job at this stage is to find out the key debates in the field.

• Who is making the most significant contribution?
• What are they saying?
• How are they saying it?
• What aren’t they saying?

 

Step Four: Notes, Notes, Notes.

Whenever you read anything you should be taking notes. Detailed notes. These need to cover the following points:

• What is the author saying?
• How is it relevant to your research?
• What are the gaps/weaknesses?
• What are the key references that you should read?

The more of these kind of standardised notes you have, the easier it will be when you write your literature review.

Step Five: Narrow Down the Field

As you read the key texts, you will begin to see what the key debates are in your field. There might be a number of ‘schools’, for example. When you become aware of them, start to focus your literature review around them.

Step Six: Filter Through Your Growing List of References

Don’t just read everything. You need to find a way to filter through the articles or books that are relevant. For example, scan the abstracts, introduction, keywords, titles and references.

Filter the sources you come across into three separate categories:

• Must read
• May read
• Probably won’t read

 

Step Seven: Use Snowball Sampling

As you read through these articles, look at their reference list. Collect articles that you think will be relevant and use them in your literature review. This is known as snowball sampling.

Step Eight: Think About the Questions that Haven’t Been Asked

You must be reading critically, which means asking what the weaknesses are and where particular articles or book could be improved. In order to tease out your own specific research topic, you need to think of the questions that haven’t been asked.

 

Step Nine: Writing Up Your PhD Literature Review

The review will broadly follow the key debates you have spotted in step five above. As you write, focus on putting in more detail about particular sources (i.e. flesh out steps six and seven). The focus when writing is to elaborate upon the key patterns and themes that have emerged.

However, you need to include your own synthesis of the material. I said earlier that you shouldn’t just summarize the literature. Instead you should write critically. You should clearly and precisely present your argument. The argument will focus around the questions that haven’t been asked – step nine above – and will ground the literature review. We’ve written a guide to being critical in your literature review. You should read it if you’re unsure what’s required. So, write early and write that first draft quickly. The earlier you start writing your literature review the better. You must accept that your first draft is going to be just that: a draft. When you write the first draft, focus on the broad structure first. This means focus on the broad themes you want to discuss in the review.

Something you need to consider is how to structure the chapter. The simple answer is that you can either structure it chronologically or thematically.

The long answer is that chronological literature reviews are restrictive and over-simplify the field. They are useful for very early drafts of the review and can help you to arrange the literature and trace threads and connections within it. However, your supervisors and examiners are looking for thematic reviews (unless they have told you otherwise), where you discuss the literature with reference to the themes that have emerged.

Equally important is knowing when to stop reviewing the literature. The sooner you go out and do your fieldwork, the better. The literature review is a cruel mistress; you’ll struggle to fully nail down its various components and fully understand how everything you have read is related. But don’t despair; aspects of the literature review will become clearer when you enter the field and start to collect data. Don’t fall into the trap of spending too long in the library and too little time doing fieldwork.

Literature Review Approaches Compared

Approach	When to Use	Strengths	Weaknesses
Thematic	Most common; organise by key themes or debates	Shows patterns across studies; highlights debates	Can lose chronological context
Chronological	When tracing how a field evolved over time	Shows development of ideas clearly	Can become a list of summaries
Methodological	When methods are contested in your field	Highlights methodological debates	May miss thematic connections
Theoretical	When comparing theoretical positions	Reveals assumptions and biases	Can be abstract for readers
Systematic	Required in health and evidence-based fields	Rigorous and reproducible	Time-intensive and restrictive

Frequently Asked Questions

How long should a PhD literature review be?

A PhD literature review is typically 8,000–12,000 words, though this varies by discipline and institution. In the sciences, it may be shorter (5,000–8,000 words). Check your university’s guidelines and speak to your supervisor about expectations for your field.

What is the difference between a literature review and a theoretical framework?

A literature review surveys and critiques existing research on your topic. A theoretical framework identifies the specific theory or model you will use to interpret your data. The literature review answers “what has been studied?” while the theoretical framework answers “through what lens will I analyse my findings?” They are complementary but serve different functions in your thesis.

How do I structure a PhD literature review?

The most effective structure is thematic — organising by key themes or debates rather than listing studies chronologically. Identify 3–5 major themes in your field, dedicate a section to each, and show how the literature within each theme supports, contradicts, or leaves gaps relevant to your research question.

How many sources should a PhD literature review include?

Most PhD literature reviews cite between 100 and 300 sources, depending on the field. The number matters less than the quality of engagement — a strong review critically analyses sources rather than simply summarising them. Aim for comprehensive coverage of key texts and recent studies.

Conclusion: How to write a PhD literature review

It’s natural to be scared of the literature review. To conduct one, you have to read, process and synthesise hundreds of thousands of words. But it’s not impossible. It becomes even easier with our free Lit Review Template & Cheat Sheet. Yours to download for free and keep forever, it’ll show you how all the components of your literature review slot together. Check it out here.

 

References and Further Reading

• Booth, A., Sutton, A. and Papaioannou, D. (2016) Systematic Approaches to a Successful Literature Review. 2nd edn. London: Sage.
• Hart, C. (2018) Doing a Literature Review: Releasing the Research Imagination. 2nd edn. London: Sage.
• Ridley, D. (2012) The Literature Review: A Step-by-Step Guide for Students. 2nd edn. London: Sage.