Arthur D. Little Case Interview Practice: Free Case and Prep Resources

Start with ADL's own practice case, Lux Flex, on its careers site: work its four exercises (a structure, a calculation, a brainstorm and a recommendation) out loud and timed before you read any solution, since ADL publishes none, and our Lux Flex walk-through below shows one way to work it. Then train what ADL says it looks for: a structure with at least two layers, fast calculation, data used well and a decisive close. On Road to Offer a free account includes 1 full AI-graded case, such as Solara Home Energy, a go or no-go on a new line with a profit target, the same shape as Lux Flex; Tessaline Water Systems (market entry) and Dunmore Cargo Bikes (market sizing) are worked cases with a model answer for every question and need no account; market sizing, case math and brainstorming drills cover the rest. Firm-style cases are practice cases written for Road to Offer or adapted from university consulting club casebooks, not the firm's own cases.

On this page, the sample case runs in your browser with no account: read it, reveal the interviewer's answers to five clarifying questions, structure it against a timer and compare it with what a strong structure covers. Then run the full version, Solara Home Energy, out loud with an AI interviewer; your first full case is free with a free account, no card. ADL's own Lux Flex case on its careers site is free too, and Tessaline Water Systems and Dunmore Cargo Bikes are free to read with a model answer for every question.

Lux Flex is the practice case ADL publishes on its careers site. Lux Flex is a high-end European gym chain with 50 sites that is thinking of opening sites under its budget brand, Penny Pressure. The page runs four exercises: build a structure (it suggests parts such as the current business, the target, customers and competition), work out what share of people who do not work out yet must join to reach a revenue target in a city of five million, brainstorm other revenue streams, and give a CEO in a hurry your findings and next steps. The page publishes no answer, so work it timed and out loud first, then check your numbers against a worked solution; our Arthur D. Little guide solves it end to end.

ADL publishes none. One reading, ours and not ADL's: the 300 million euro market at 360 euros a member a year is about 833,000 existing members; 25% of that market is 75 million euros, so the remaining 135 million euros of the 210 million euro target needs about 375,000 new members; against about 4.17 million people who do not use a gym today, that is about 9%. The number depends on the assumption that every resident outside the existing members is a non-user, so say it out loud and ask the interviewer to confirm it. Reaching a revenue target also does not prove the launch is profitable, so name the next test.

ADL's pages do not say. Prep guides describe ADL cases as mostly interviewer-led, with some candidate-led cases. ADL's own tips still ask you to ask for time to structure, present at least two layers, request data when you need it and think out loud, so practise building your own structure and also answering one directed question at a time.

It depends on the office and role. The Paris Business Analyst internship posting lists an online case interview, two in-person case interviews and a final interview with a Principal. The London internship posting lists five stages: an online assessment, a first interview, a case study assessment, a presentation and a senior interview. ADL's global pages give no number, so ask your recruiter for your schedule.

For some roles. The London Business Analyst internship posting lists an online assessment of analytical and problem-solving capabilities and, later, a presentation of your findings and recommendations; the Paris posting lists an online case interview instead. Neither names a provider or time limit. Road to Offer has no Arthur D. Little test simulator; the closest practice is our case math, market sizing and brainstorming drills and a full case out loud.

Not unless ADL says so. The London internship posting says ADL embraces the responsible use of AI in its work, but that using AI tools during interviews, online assessments, case study exercises or presentations is not permitted unless explicitly authorised, and that candidates found doing it will not be considered further. Use practice tools beforehand and follow the instructions you are given on the day.

Four things, in ADL's words: how your mind works and your intellectual curiosity, your ability to solve problems with critical thinking and a proactive nature, how you use the data and how quick you are with calculations, and the approach you take and how confident you are in your solutions. ADL adds that it uses the case to assess your ability as a consultant, not your business sense or sector knowledge, although its behavioral interview page describes the case as focused on business sense and approach to problem-solving. Prepare for a sound method rather than industry facts.

ADL's behavioral interview page lists six examples: why you want to work with ADL, what company is having a tough time now and what you would recommend, what attributes you would bring to a case team, what experience you are most proud of, what experience you wish you could do over and how, and what makes a good management consultant. Prepare a specific Why ADL answer and two or three stories with numbers in them, and say them out loud; Road to Offer's fit practice asks questions like these with follow-up probes, 1 session free with a free account.

Candidates report them, and ADL's own Lux Flex case contains one in all but name: a city of five million people and a market of 300 million euros, and a question about the share of non-users who would have to join. ADL's tip for that exercise is to drop the zeroes and write 1M for 1,000,000 when adding large numbers quickly. Practise market sizing and quick math daily.

ADL's careers site describes the next generation consultant as an entrepreneur who takes ownership, an ambidextrous mind that balances creativity and rigor, a breakthrough creator, a side-by-side master who helps others do their best work, a bridge builder and a sustainability ambassador. The Paris internship posting adds curious, ambitious, proactive and rigorous, with strong teamwork skills. Choose two or three stories that show those traits, with a number in each.