How do you prepare for a dissertation defense?
Prepare by auditing your own argument before the committee does. For each major claim, know the supporting evidence, the contradicting evidence, the methodological weakness, and your honest response. Most difficult defense questions target places where the author already sensed a soft spot and hoped it would not come up.
Audit claim by claim
Walk your dissertation and list every substantive claim. For each: what supports it, what contradicts it, how strong is that evidence, and where is it vulnerable?
The claims where you cannot answer quickly are precisely the ones to prepare. Your discomfort is a reliable index of committee interest.
Expect questions by category
Theoretical, methodological, statistical, epistemological, ethical, literature coverage, limitations, generalizability, contribution, and future research.
Prepare at least one honest answer in each category. 'That is a limitation, and here is how I would address it in future work' is a strong answer, not a weak one.
Rehearse being wrong
The failure mode in defenses is not ignorance — it is defensiveness. A candidate who concedes a genuine limitation gracefully reads as a scholar; one who argues every point reads as brittle.
Practice conceding. It is a skill, and it is the one most often untested before the day.
Common questions
What is the most common defense question?
Some form of 'why this method?' — a request to justify methodology against the alternatives you did not choose.
Should I memorize answers?
No. Know your evidence well enough to reason in the room. Memorized answers fail as soon as the question is phrased unexpectedly.