Assessment Centre Case Study Exercises: How to Prepare and What Good Looks Like

The case study is the exercise candidates worry about most at an assessment centre, and the one they prepare for least effectively. Interviews can be rehearsed question by question. The case study feels unrehearsable: a brief you have never seen, data you have never touched, and a clock that starts the moment you begin.

It is more learnable than it looks. Case studies at graduate and early-career assessment centres follow a small number of patterns, and assessors score a small number of things. Once you know both, practice stops being guesswork.

What the exercise actually is

You are given a short business scenario: a company facing a decision, usually with two or three named options. Alongside the scenario sit a handful of exhibits, typically small tables or charts covering revenue, costs, customer numbers or market data. Your job is to recommend a course of action in writing, under time pressure, usually in 30 to 60 minutes (some centres run tighter exercises of 10 to 15 minutes of writing after untimed reading).

The scenario is fictional but realistic. A retail chain deciding whether to close stores or invest in delivery. A software firm choosing between two markets. A council service weighing an outsourcing decision. You are not expected to know the industry. Everything you need is in the pack.

What assessors are scoring

Assessors mark against criteria, not vibes. Across employers the criteria are remarkably consistent:

• Did you answer the question? A surprising number of candidates describe the situation at length and never commit to a recommendation. A clear decision, stated early, scores. Hedging does not.
• Did you use the numbers? The exhibits exist to be used. Two or three simple calculations (a margin, a trend, a comparison) lift an answer more than any amount of polished prose.
• Did you weigh both sides? Good answers acknowledge the strongest argument against their recommendation and explain why it does not win.
• Is it structured? Recommendation, reasoning, risks, next steps. Assessors read dozens of these in a day: structure is legibility.
• Is it commercially sensible? Not brilliant. Sensible. Does the recommendation survive contact with common sense about money, customers and people?

Notice what is missing: originality. The case study is not a creativity test. Choosing the defensible option and defending it well beats choosing the clever option and running out of time.

How to work the brief

Read the task question first, before the scenario. Knowing what you must produce changes how you read everything else.

Then read the scenario once, quickly, and go straight to the exhibits. For each one ask a single question: what does this table want me to notice? Exhibit designers are not subtle. A cost line growing faster than revenue, one product carrying the rest, a customer segment quietly collapsing. Each exhibit usually contains one finding, and the third exhibit often carries the tension that should shape your recommendation.

Do the arithmetic roughly and visibly. If revenue is 4.2m and costs are 3.9m, the margin is thin: say so and use it. You are not expected to produce spreadsheet precision in your head, and mental arithmetic level numbers are chosen deliberately.

Then write to a skeleton you have decided before the day:

1. Recommendation: one sentence, first line.
2. Reasons: two or three, each anchored to an exhibit.
3. The other side: the best argument against, and why it loses.
4. Risks and next steps: what could go wrong and what you would check first.

A structured 350 word answer beats an unstructured 700 word one every time. Length is not the metric; decision quality per minute is.

The failure modes to train out

• Narrating instead of deciding. Summarising the brief back to the assessor spends your minutes proving you can read.
• Ignoring the exhibits. An answer with no numbers in it reads as an opinion piece.
• Balancing forever. For and against lists with no verdict score poorly on the one criterion that matters most.
• Losing the clock. Most candidates spend too long reading and are still mid-argument when time is called. An unfinished answer with no recommendation is the worst outcome available.

A practice plan that works

Reading about case studies does not build the skill; doing them under a clock does. Three or four timed attempts is usually enough to feel the difference, because the skeleton becomes automatic and your reading gets sharper each pass.

If you can, practise in conditions that mirror the real thing: an unseen brief, real exhibits, a hard time limit, and scoring against the criteria above rather than a generous friend saying it reads well.

That is exactly what our mock assessment centre runs: a timed written case study with exhibits, scored the way an assessor scores it, followed by the interview and presentation stages. Two or three runs before the real day and the format stops being frightening, which frees your attention for the thinking.

For the interview stages that usually sit alongside the case study, see our guides to competency interviews and group exercises.