PhD Viva Questions: What Examiners Actually Ask

PhD viva questions are rarely a secret list you can memorise. Examiners are trying to understand your thesis, test the strength of its argument and evidence, and establish that you can explain and defend the work as an independent researcher.

That means the most useful preparation is not rehearsing fifty perfect speeches. It is practising how to explain the major decisions in your thesis: why this problem, why this literature, why these methods, what you found, what you contributed and what you would change.

Viva formats and regulations vary by university and country. Always read your institution’s formal examination rules. For preparation, Oxford’s DPhil viva guidance recommends taking preparation seriously and prioritising areas where you feel less confident.

Table of Contents

The questions almost every thesis needs to answer

If you can discuss these seven areas clearly, you can handle a large proportion of viva discussion:

What problem did you investigate?
Why did it matter?
How does your work relate to the existing literature?
Why did you choose these methods?
What did you find?
What is the original contribution?
What are the limitations and implications?

Opening viva questions

Examiners may begin broadly to help you settle into the discussion.

Can you summarise your thesis in a few minutes?
What is the central argument of your thesis?
What motivated you to study this topic?
How did the project change from your original proposal?
What are you most proud of in the thesis?
If I remember only one thing from this thesis, what should it be?

Prepare a two-minute and a five-minute version of your thesis explanation. The short version forces you to identify the backbone of the work; the longer version gives you room for evidence and contribution.

Questions about your research gap and contribution

What gap does the thesis address?
How did you establish that this gap existed?
What is original about your work?
Is the contribution theoretical, empirical, methodological or practical?
Which finding makes the strongest contribution?
How does your contribution change what researchers should think or do?
How far can the contribution be generalised?
What would the field lose if this research had not been done?

Avoid answering “nobody has ever studied this exact topic.” Originality is stronger when you can show what existing research could not explain and how your thesis improves that position. See how to find and defend a research gap.

Literature-review questions

Why did you include these bodies of literature?
Which authors or theories most influenced the thesis?
Which literature do you disagree with, and why?
Has important work appeared since you completed the review?
How did your understanding of the field change during the PhD?
Why did you exclude a particular theory or body of research?
Where is the strongest disagreement in the literature?

You do not need to pretend that your review froze on submission day. If relevant work has appeared, explain how it affects the interpretation of your thesis rather than panicking because it is not cited.

Methodology questions

Why was this methodology appropriate to the question?
What alternatives did you consider?
How did you select participants, cases, datasets or texts?
What were the most important assumptions in your method?
How did you address bias, validity, reliability or trustworthiness?
What ethical issues did the research raise?
What would you change about the method if you repeated the study?
Which methodological limitation matters most for interpreting the results?
Could another researcher reproduce or audit your analysis?

A strong answer often has three parts: decision → reason → consequence. Explain what you chose, why it fit the question, and what that choice allowed or limited you to claim.

Results and analysis questions

Which result surprised you most?
Which finding is most robust?
Were any results inconsistent with your expectations?
How did you decide what counted as meaningful evidence?
Could an alternative explanation account for the result?
How do the findings relate to previous studies?
Are there findings you chose not to emphasise?
How sensitive are the conclusions to your analytical choices?

Questions about limitations

What is the biggest limitation of the thesis?
Why did you accept that limitation?
Does it threaten the central conclusion?
What can you not claim from these results?
How could future research address the limitation?

Do not respond to a limitation as if you have been caught. Every research design trades some possibilities for others. Show that you understand the boundary and have kept your claims inside it.

Future-research questions

What should be done next?
Which unanswered question is now most important?
How would you design the next study?
Which part of the thesis could become a publication?
How could the work be applied in practice?
Has the field changed enough that you would frame the project differently now?

Difficult or challenging questions

An examiner may press on a weak point, challenge an assumption or offer an interpretation you do not share.

You can respond without becoming defensive:

Pause before answering.
Restate the question if you are unsure what is being asked.
Separate what the thesis shows from what you infer.
Acknowledge a genuine weakness clearly.
Explain your reasoning where you still defend the choice.
Say when you do not know.

A University of Reading account of viva preparation recommends thinking of the viva as an academic discussion and practising the “what, why and how” of the research rather than viewing examiners as adversaries. Read their peer-to-peer viva advice.

A practical answer framework

For many questions, use this four-part structure:

Answer: give the direct answer first.
Evidence: point to the thesis, data or literature.
Boundary: state what the evidence does not establish.
Implication: explain why the answer matters.

Example:

“I chose interviews because the research question concerned how participants understood the policy rather than how frequently a behaviour occurred. The semi-structured format let me compare core topics while following unexpected explanations. The limitation is that the study cannot estimate prevalence across the whole workforce. Its contribution is therefore explanatory rather than population-level.”

Questions to practise from every chapter

Open each thesis chapter and write answers to:

Why is this chapter here?
What is its central claim?
What evidence supports that claim?
What is the weakest point?
How does it connect to the chapter before and after?
What would change if this chapter were removed?

Do you need to memorise answers?

No. Memorised answers can become brittle when an examiner asks the same issue from an unexpected angle. Practise explaining ideas aloud instead. You want familiarity with the argument, not a script.

The companion guide, how to prepare for your PhD viva, gives you a staged preparation plan, thesis-marking system and day-before checklist.

A copyable viva question sheet

Central thesis in one sentence:
Contribution in one sentence:
Most important finding:
Strongest chapter:
Weakest chapter:
Biggest methodological trade-off:
Most important limitation:
Key theory I rely on:
Key theory I challenge:
Result that surprised me:
Alternative explanation:
What changed since submission:
One thing I would redesign:
Most valuable future study:
What I want examiners to remember:

If presenting your work aloud is the part that worries you, the academic conference presentation guide is also useful for practising concise explanations and responding to questions under pressure.