Every year, thousands of PhD students and postdocs join labs without enough information. Not because they were not careful. Because the information was not available to them. Public profiles show publications and grants. Lab websites show smiling group photos. None of that tells you what it actually feels like to work there.
These five questions will not guarantee a good experience. But asking them honestly, and paying attention to how they are answered, will give you information that most researchers only wish they had asked.
The Five Questions
Can I speak with two or three former lab members, not current ones?
Current lab members are unlikely to speak freely. Former members have nothing to lose. A supervisor who hesitates to connect you with former lab members, or who can only offer current students, is giving you information without saying a word. A confident supervisor will connect you immediately and without conditions.
What happens if my project is not working after one year?
This question reveals how a supervisor handles failure, which is inevitable in research. A good answer involves scientific problem-solving, regular check-ins, and a willingness to pivot. A concerning answer involves pressure, blame, or vague reassurance. How a supervisor responds to this hypothetical tells you how they will respond to the real thing.
How often do you meet one-on-one with your students or postdocs?
Regular individual meetings are one of the strongest predictors of a positive supervision experience. If the answer is "whenever you need me" without a structured frequency, that often means rarely. You want a supervisor who treats meetings as a commitment, not a favour.
Where are your former PhD students and postdocs now?
This is one of the most revealing questions you can ask and one of the least asked. A supervisor who has trained many people but cannot name where they ended up, or whose former mentees have left academia at unusually high rates, is telling you something important. Strong mentors know where their people are. They are proud of it.
What do you expect from someone in this role outside of working hours?
Ask this directly. The answer will be more honest than you expect. Some supervisors will tell you plainly that weekends are working days. Others will say they respect personal time and mean it. You deserve to know before you sign a contract, not six months in when you are already dependent on their funding and recommendation.
One Final Note
No set of questions will eliminate risk entirely. Some supervisors perform well in interviews and differently in practice. Some labs that look difficult from the outside are deeply supportive on the inside. Context always matters.
What these questions do is shift the balance of information slightly in your favour. In a relationship defined by power imbalance, any information you can gather before committing is worth having.
If you have worked with a supervisor and want to share what you found, honestly and anonymously at rateyourpi.com. That information is the most valuable thing you can contribute to the next researcher making this decision.