The case interview, explained

The case interview is the centrepiece of consulting recruitment because it mirrors the job: you're dropped into an unfamiliar problem with messy information and asked to produce a clear recommendation under time pressure.

What they're actually assessing

Interviewers are watching for four things:

1. Structure — can you break a vague problem into logical, MECE (mutually exclusive, collectively exhaustive) parts?

2. Quantitative comfort — can you do clean mental maths and interpret what the numbers mean?

3. Business judgement — do your recommendations make commercial sense?

4. Communication — are you clear, calm and easy to follow?

A structure that travels

Forget memorising twenty frameworks. Most cases yield to a simple habit:

• Clarify the objective. What does success look like, in numbers? Don't start solving until you know.
• Build a tailored structure. Take 30–60 seconds, write down 3–4 buckets that fit *this* problem, and walk the interviewer through them.
• Dive into the most important branch first. Drive the analysis; don't wait to be led.
• Synthesise as you go. State what each finding *means*, not just the number.
• Recommend. End with a crisp answer, a reason, and a risk or next step.

Maths without panic

Practise estimation out loud. Round sensibly, label your units, and sanity-check the result. "£2.4bn market, 8% share, so roughly £190m revenue" beats a silent, error-prone calculation every time.

How much to prepare

The average successful MBB candidate completes 30–50 practice cases. Crucially, practise out loud with a partner — thinking silently does not prepare you for articulating under pressure. Quality of feedback matters more than raw volume.