The McKinsey Personal Experience Interview (PEI) differs from a standard behavioural interview mainly in depth. Instead of several short STAR answers, you typically discuss one experience for around 10–15 minutes while the interviewer probes your specific actions, reasoning and feelings. McKinsey's own guidance asks candidates to prepare two examples for each of four areas, to focus on their specific role, to lead with reasoning rather than actions, and to have a conversation rather than present a rehearsed story.
What is the McKinsey PEI?
According to McKinsey's careers site, interviews for most client-facing roles include personal experience interviews and problem-solving (case) interviews, and some roles add an expertise interview. McKinsey advises preparing two personal examples for each of four areas. Several prep providers report that McKinsey renamed these four dimensions in mid-2025 to Leadership, Connection, Drive and Growth (previously described as inclusive leadership, personal impact, entrepreneurial drive and courageous change).
How does a standard behavioural interview work?
At many companies, a behavioural or competency interview asks several questions, such as "Tell me about a time you led a team", "Describe a conflict" and "Give an example of failure", and expects a two-minute STAR (situation, task, action, result) answer to each. Follow-ups are often light.
What are the key differences?
| Standard behavioural | McKinsey PEI | |
|---|---|---|
| Number of stories | Several per interview | Usually one in depth |
| Time per story | ~2 minutes | Often ~10–15 minutes |
| Follow-ups | Few | Many, detailed |
| Focus | What happened | Why you did it, how, and what you thought and felt |
| Repetition | Stories may be reused | Prepare different stories for different interviews |
What do PEI follow-up questions look like?
Expect probes such as:
- "What exactly did you say to them?"
- "Why did you choose that approach rather than escalating?"
- "What was the other person's reaction?"
- "What would you do differently now?"
- "How did you feel at that moment?"
- "What were the alternatives you considered?"
These questions test authenticity. Embellished or borrowed stories collapse under this level of detail, which is one reason McKinsey's AI guidance explicitly lists "exaggerating or creating achievements that aren't yours" as not allowed.
How do you choose a good PEI story?
The best stories have:
- Real stakes: something genuinely mattered and the outcome was uncertain.
- Your clear personal role: "I" not "we". McKinsey's own blog tips stress focusing on your role and not over-investing in context.
- Tension: resistance, disagreement, setbacks or a difficult person.
- Choices: points where you weighed options and decided.
- A result and reflection: what happened and what you learned.
Stories don't need to be corporate. Societies, sport, volunteering, family responsibilities and part-time jobs are all fine if the challenge was real.
How should you structure the opening of a PEI answer?
Spend no more than about a minute on context, then move to the challenge and your actions. A useful flow:
- Headline: "I'll talk about persuading our university's estates team to reverse a decision to close a student study space."
- Brief context and stakes
- The challenge and your goal
- Your actions, with reasoning: McKinsey asks candidates to "lead with reasoning, not actions", so explain why at each step
- Outcome: quantified where possible
- Reflection
How do you prepare for depth?
For each story, write notes covering:
- Key people and their positions
- Exact conversations, with approximate words
- Two or three decision points and the alternatives you considered
- Obstacles and how you overcame them
- Measurable outcome
- What you'd do differently
Then have a friend ask "why?" and "what exactly did you do?" five times in a row. If you run out of detail, choose a different story or reconstruct it more carefully. Never invent detail.
How does this compare to other firms?
BCG and Bain also assess fit and behaviour, sometimes with similar depth, though formats vary by office. Bain's experience interview is often described as structured around specific dimensions. Big Four and boutique firms more often use standard competency questions. The PEI approach of preparing deep, multi-layered stories improves your performance in all of them.
How should you practise?
Practise out loud with probing follow-ups, which is exactly what is hard to simulate alone. An AI interviewer such as caize.ai can run PEI-style sessions that keep asking "why" and "what exactly did you do", so you can find thin spots in your stories before a real interviewer does. Combine this with at least a few human mocks, ideally with people who have done PEIs.
FAQ
How many PEI stories should I prepare?
McKinsey suggests two examples for each of the four areas, so about eight. Have a few spares.
Can I reuse a story across interviews?
Prepare enough to avoid repetition. Many coaches advise against reusing a story with different interviewers in the same process.
Does the PEI matter as much as the case?
McKinsey interviewers commonly stress not to neglect it. Treat it as equally important.
Should my story be from work?
Not necessarily. Any experience with genuine challenge and clear personal impact can work.
