Short answer: a defined subset of your questions already exists in writing before you enter the room. At UBC the external examiner is asked to supply questions with the report, and the chair must ensure they are addressed. The rest come from examiners whose roles determine what they ask — which is why the room is more predictable than it feels.
Most defence advice is about nerves. This article is about the mechanics, because the mechanics are published, they are specific, and they tell you what is coming.
Who is actually in the room?
Composition varies, but the Canadian pattern is consistent. UBC states that the examination committee normally consists of an external examiner (welcome at the defence, but not required to attend), two university examiners, two or three members of the supervisory committee including the research supervisor, and an examination chair.
Quorum at UBC is narrower than the full committee: the chair, two approved university examiners, and two members of the supervisory committee. Note who is not on that list. The external examiner — the person whose written report decided whether you got to this stage at all — may not be present.
At McGill the chair has a specific title and a specific limitation. The Pro-Dean represents the Dean of Graduate and Postdoctoral Studies and chairs the committee, and McGill notes that all committee members except the Pro-Dean are expected to have read the thesis. The person running your defence is deliberately not one of the people judging its content.
How long does it run, and in what order?
UBC publishes the structure as: the candidate makes a public presentation of the dissertation (maximum 30 minutes); examining committee members question the candidate; members of the audience are invited to ask questions; the committee holds an in-camera discussion and decides its recommendation; the chair conveys that recommendation to the candidate. UBC adds that the Oral Defence “usually takes two to two and a half hours,” that candidates are encouraged to arrive 30 minutes early, and — worth reading twice — that “the doors to the exam room are closed at the start of the exam and no one may enter the exam room, either physical or virtual, once the Final Oral Defence has begun.”
McGill divides the same event into three parts: a private pre-defence meeting, an open public session, and a private evaluation session. The presentation is 20 minutes, summarising the research question, the results and the conclusions, and “should focus especially on the original contributions to knowledge.” The question period “usually 60-90 minutes.” The closed deliberation runs for a maximum of 60 minutes.
| Element | UBC | McGill |
|---|---|---|
| Presentation | Maximum 30 minutes | 20 minutes |
| Question period | Committee, then audience | Usually 60–90 minutes |
| Chair | Examination chair, represents the Dean | Pro-Dean, represents the Dean |
| Whole event | Usually 2 to 2.5 hours | Three parts, closed session max 60 min |
Why do some of the questions already exist in writing?
This is the single most useful thing to know, and almost nobody preparing for a defence acts on it.
Among the external examiner’s listed responsibilities at UBC is to “provide questions to be asked at the Final Oral Defence,” and — critically — “if the external examiner is not able to attend, these questions will be asked by the research supervisor.” The chair’s own listed duty is to “ensure that any questions raised by the external examiner are addressed by the candidate during the question period.”
So the external’s questions are not optional, not improvised, and not skippable. They are written, they arrive with the report, and someone in that room is obliged to put them to you.
McGill makes the choreography explicit from the other side: the Pro-Dean and the committee meet privately beforehand “to determine the Unit’s normal procedures for the order of questions, time alloted for each question and for subsequent rounds of questions, and reading of the external examiner’s questions.”
The practical move: ask your supervisor what the external examiner’s report says, and specifically whether it contains questions. Many Canadian programmes release the report or its substance to the candidate before the defence; some do not, and where the answer is no, your supervisor has still read it and can tell you which two chapters drew comment. Preparing against a document that exists beats preparing against your imagination.
What does each examiner role ask?
Match the question to the role and the room stops being random.
The external examiner: is this a contribution?
Their assigned job at UBC is to assess whether the dissertation meets the criteria for a successful dissertation, review its strengths and weaknesses, and recommend whether the candidate proceeds. Their questions therefore sit at the level of the whole work.
- What is the original contribution to knowledge here, in one sentence?
- Where does this sit in the international literature, not just the Canadian literature?
- Which of your findings would survive if your central assumption were wrong?
- What would you publish from this first, and in which journal?
- What is the weakest chapter, and why did you keep it?
The university examiners: does this meet the university’s standard?
UBC’s list of their responsibilities is unusually revealing. They “represent the broad academic standards of UBC,” must “maintain an arm’s-length relationship with the candidate throughout the examination process,” and must “avoid discussing the candidate’s research with either the candidate or any member of the supervisory committee until the Oral Defence begins.”
That last rule is the one that shapes their questions. They come to your work cold, from outside your subfield, having read only what you wrote. So they ask the questions your supervisor stopped asking two years ago because the answer had become obvious inside the project.
- Explain your central concept to someone in a different discipline.
- Why this method rather than the obvious alternative?
- How did you handle missing data, and what did that do to your conclusions?
- Your sample is drawn from one setting. What exactly can you generalise, and to whom?
- You report a reliability coefficient of .68 here. Is that acceptable, and on what basis?
- Page 143 says one thing and page 201 seems to say another. Which is right?
The threshold questions in that list are where unprepared candidates lose ground, because the honest answer requires knowing the convention rather than the number — our guide to what counts as an acceptable Cronbach’s alpha works through exactly that case.
Your supervisory committee: can you defend the decisions we watched you make?
They know the project. Their questions are usually the ones that let you show command, plus anything the external raised that they want on the record.
- Why did you change your design after the pilot?
- What would you do differently if you started again?
- Where do you go next with this?
The chair: procedure, not content
The chair does not examine you. At UBC the chair represents the Dean, ensures the exam follows policy, ensures the external’s questions are addressed, moderates the closed discussion and conveys the outcome. If the chair speaks to you, it is about process.
Which questions are guaranteed?
Three, in some form, at almost every Canadian defence.
- “Summarise your contribution.” Often the opening question and often answered badly, because candidates describe what they did rather than what is now known that was not known before. Write two versions in advance: thirty seconds and two minutes.
- “Why this method?” Not “explain your method” — why this one. The answer names the alternative you rejected and the reason. Where your design involved human participants, expect the ethics reasoning to be part of it; our guide to REB approval and TCPS 2 sets out the decisions a committee will assume you made deliberately.
- “What are the limitations?” A candidate who names three real limitations, unprompted and without flinching, closes the topic. A candidate who minimises them invites the committee to find a fourth.
Since 2024 a fourth has become common at Canadian graduate schools: an examiner may ask you to describe and defend any use of generative AI in the research or writing. Both major published Canadian guidances treat that as examinable, and the rules are set out in our guide to what Canadian universities actually permit for AI in a thesis.
How should I answer?
McGill’s guidance is more concrete than most preparation advice: the student may use notes and audiovisual aids according to the norms of the discipline, but “reading from a script is frowned upon”; any visual presentation “should be structured as for a presentation at an international conference”; the student “should have a copy of the thesis on hand, as there may be questions related to specific points in the thesis”; and “answers to questions should be concise, unless there is a request to elaborate. The idea is to engage the members of the Committee in a rich and scholarly discussion.”
Two behaviours follow. Bring the thesis, tabbed, because a page-specific question answered from the page reads as command. And answer short. A four-minute answer to a one-minute question uses up goodwill and invites interruption; a concise answer that invites a follow-up produces the discussion the committee is actually there to have.
What are the possible outcomes?
They differ by institution, and reading your own is worth ten minutes.
McGill publishes four: Passed; thesis not passed (the defence was satisfactory but the thesis was not — the student may submit a revised thesis within six months, evaluated without another oral defence); oral defence not passed (the thesis was satisfactory but the defence was not — another oral defence within six months, no revised thesis); and thesis and oral defence not passed. Where only minor stylistic or editorial revisions are needed, the Pro-Dean delegates one committee member, usually the supervisor, to verify them.
UBC separates the two judgements as well, asking the committee to evaluate the defence and the dissertation and then to choose an overall recommendation of a pass or a re-examination, noting that “no more than one subsequent attempt is permitted.”
The structural point worth carrying into the room: your thesis and your performance are marked separately. A weak answer does not undo a strong thesis, and a polished presentation does not rescue a thesis the external found unsatisfactory.
Does any of this vary by university?
Yes, and one Canadian graduate school has now said so in public. The University of Toronto — where, by its own count, more than 1,000 final oral examinations take place every year — began a review of its final oral examination in January 2024, and the resulting working-group report states that the coexistence of the SGS Calendar and the SGS FOE Guidelines creates “confusion between what exactly are the regulations versus what are the suggested best practices,” with the consequence that “some inconsistencies in application of these regulations and guidelines across divisions are observed.”
That report is out for consultation, so its recommendations are proposals rather than rules. But the diagnosis is a published fact and it has a direct implication for you: generic defence advice, including this article, is a starting point. The binding document is your own graduate unit’s, and the person who can tell you how it is actually applied is the graduate coordinator who calendars these examinations. U of T also uses a different term — external appraiser rather than external examiner — which is a small reminder that even the vocabulary is local.
Whichever track you are on, the requirements attach to the credential rather than to the word on the cover page; our guide to thesis, dissertation or major research paper in Canada sets out which programmes involve an oral examination at all.
Before any of that, the document has to be finished and internally consistent, because a page-143-versus-page-201 question is created months earlier by a chapter that moved. Draft your thesis in Tesify and keep structure, tables and references consistent while every argument remains 100% written by you.
Frequently asked questions
How long is a thesis defence in Canada?
UBC states that its Final Oral Defence usually takes two to two and a half hours. At McGill the presentation is 20 minutes, the question period usually runs 60 to 90 minutes, and the closed deliberation is capped at 60 minutes.
Do I get the external examiner’s questions in advance?
The questions exist in advance — the external is asked to supply them — but whether you see them depends on your programme. Ask your supervisor, who has read the report.
What if the external examiner does not attend?
Their questions are still asked. At UBC, if the external cannot attend, the research supervisor puts those questions to the candidate.
Can I be late for my own defence?
No. UBC closes the doors at the official start time and states that no one may enter the room, physical or virtual, once the defence has begun. Arriving 30 minutes early is the published advice.
Are audience questions allowed?
Yes at UBC, where members of the audience are invited to ask questions after the committee. At McGill the Pro-Dean may invite audience questions, taking the unit’s practice into account.
Can my defence be in French?
At UBC the Final Doctoral Examination is a public event conducted in English, though for theses in language programmes some questions may be posed or answered in the language concerned provided the committee can follow proceedings. Francophone Quebec universities run their examinations in French. Check your own institution.
Is the chair going to examine me?
No. The chair represents the Dean and manages procedure: ensuring the exam follows policy, ensuring the external’s questions are addressed, moderating the closed discussion and conveying the outcome.
What happens if I fail?
Institutions distinguish between failing the thesis and failing the defence. McGill allows six months to submit a revised thesis or to re-defend on a first Not Passed; UBC permits a re-examination, with no more than one subsequent attempt.
Do I need to memorise my presentation?
No, and you should not read one either — McGill’s guidance states that reading from a script is frowned upon. Know your opening and closing verbatim and speak the rest.
How many people are on the committee?
At UBC, normally an external examiner, two university examiners, two or three supervisory committee members, and a chair, with quorum requiring the chair, two university examiners and two supervisory committee members.
Will they ask about things outside my thesis?
They may. McGill states that questions will be based mainly on the thesis and presentation, but that the student’s grasp of related subjects may also be tested.
Should I attend someone else’s defence first?
Yes. UBC explicitly recommends it, calling attendance at a defence in a nearby field an excellent way to learn what to expect, and publishes a list of upcoming exams.