Consulting case study interviews

For a management consulting job, you are likely to have three to five interviews, of which two to four will probably involve a case study. The case study section of a one-to-one interview can last between 10 and 30 minutes, and you might even have two case studies within a half hour interview.

For a case study your interviewer will present a situation or question to explore and resolve either orally, or in writing, or both. For example:

• How would you choose the optimal balance of economy/business class seats on an airline?
• What strategy should a New World wine producer use when seeking to enter a European market?
• How many washing machines are sold each year in the UK?

The question may be as brief as those above, may be a slightly more specific business problem explained to you verbally, or may require preparation by reading related documents right before the interview. Occasionally, the interviewer may ask you about the business issues linked to something from your own background, so be prepared!

Case studies simulate aspects of consulting assignments and may even be based on a recent project led by the interviewer. Each case allows the recruiter to assess your capability and performance and you will need to perform well on a number of case studies to secure an offer of employment.

Consulting companies look for engagement, energy, and interest in the problem under discussion as well as working through the question at hand. Remember, the interviewer is likely to be someone who manages consulting projects day-to-day (‘Job Manager’, ‘Engagement Manager’, ‘Senior Associate’) and so one of the judgements they will be making is whether or not you are someone they would want on their team, and someone they could introduce to the client.

Top tips

• Clarify. You’ll need to understand the problem and its component parts sufficiently to get started. Only if absolutely necessary should you seek extra information or clarification. It’s a good idea to briefly state your understanding of the problem in your own words. The case may appear simple and with no data (for example, ‘What would you think about in setting up a new coffee shop in Oxford?’) or very complex with pages of printed charts and graphs. It is much better to make assumptions (aloud) and get started, such as, ‘We are looking at burger sales in Europe; this is a large market so I propose to focus first on England and then extrapolate the results’.
• Take the lead. The interviewer wants to see if they’d like you on their team so show them that you can take the initiative.
• Think out loud. The interviewer wants and needs to know what you are thinking. They are not telepathic so describe out loud what you are thinking every step of the way. However, think before you speak, so the thoughts that you do share demonstrate your judgement.
• Write things down. Make sure you have an A4 pad of paper and pen/pencil. As you think and talk, write large and legibly, in note form so the interviewer can follow what you are doing and perhaps join in. Leave lots of space so you can add new thoughts as the case develops. Don’t be afraid to start new sheets and draw pictures/sketch graphs/block diagrams.
• Landscape paper. We recommend that you use the paper in a landscape orientation. You can move left to right across the page(s) with Structure –> Hypotheses –> Data –> Recommendations, which will mirror how consultants’ presentations appear. You may well need more than one sheet.
• State your approach. It’s not so much the answer you get but the process you use to get there. Avoid the temptation to answer the case immediately with a possible solution – consultants have to show they have been thorough and demonstrate how they have explored every option. In the jargon it’s ‘MECE’ (pronounced “meesee”): Mutually Exclusive and Collectively Exhaustive.
• Explain. Once you are clear about the problem, explain how you are going to approach it. List some top-level topics either down the left hand side of the (landscape) page working towards the right hand side with more details, or, work from top to bottom (portrait). Either way, the key is to clearly show your thinking.
• Ask. After you have laid out the structure and demonstrated that you can take the lead on the problem, ask if the interviewer wants you to focus on a specific area or has more information for you. This can be a full three to five minutes after you start; don’t be tempted to ask for help sooner as that shows you need lots of guidance and would be interpreted as someone who does not take initiative and would not pull their weight on the interviewer’s team.
• Listen. Be ready to listen and respond to any direction that your interviewer may give you in response to your proposed analysis. The structure you recorded on paper will help you to remain focused and provide you with a ’map’ or reference point if you get diverted or distracted. Also, if/when you think of topics you missed, you can add them to your structure. Most importantly it will demonstrate to the interviewer that you have the logical thinking and analytical skills they seek.
• Develop hypotheses. Don’t try to answer the question directly but develop hypotheses to which you may not have the answer, for example,  ‘prices are higher than competitors’ and ‘revenues have dropped because volume has dropped’. Keep talking as you develop all this.
• Suggest data you would need to prove/disprove the hypotheses. Sketch some simple charts, for example, ‘I’d need to know sales of car tyres over the last three years,’ then draw an x-y chart, with time along the x axis and sales up the y axis. Then guess some lines, for example, sales rising over the three years. You don’t have to know the actual data (how could you?) but you can say, ‘If sales have done this, then…’.
• Develop some recommendations. Once you have found/agreed some data, it’s time to move to the final stage, recommendations for the client. ‘If I were working with a client considering opening a new coffee shop in Oxford, based on these data, I would recommend…’.
• Be comfortable working with numbers! If you have not used them for a while, make sure you are especially comfortable with percentages, ratios, long division and multiplication, estimates, and working with large numbers. Dust off your mental arithmetic skills. Be happy to round to one or two significant figures. Make sure you know some rough data, such as populations of UK (+/- 70 million), London (+/- 9 million), EU (+/- 450 million), USA (+/- 340 million); size of a football field (+/- 7,000m²) or length of a jumbo jet (+/- 70m); weight of a human (+/-70kg). It is also a good idea to use the metric system to avoid confusion with units.
• Use your common sense. You may not have any business experience in the areas that the case study covers, so instead make use of any perspectives that you may have acquired from being either a user or a consumer of the products and services that are the subjects.
• Be ready and willing. Be prepared to respond to further interviewer requests as you go along, e.g. to brainstorm ideas or to work through some estimates of market size. Positive energy, engagement and enthusiasm (perhaps even enjoyment!) are important indicators that you are more likely to thrive in a consulting career.

Remember, case studies are a skillset, not a script. Go in with the mindset that something might surprise you. With careful preparation, and following the framework above, you can increase your chance of successfully navigating case study interviews with confidence.

Frameworks

In your research and reading you are likely to come across analytical frameworks that can help. Some basic frameworks include:

• SWOT analysis: strengths, weaknesses, opportunities, threats
• 4 Cs: customers, costs, capabilities (of the organisation), competition
• 7 Ps of Marketing: product, price, promotion, place, packaging, positioning and people
• Porters five forces

Check the stance of companies you are targeting. Many have published their policies on AI on their websites. Some firms strictly prohibit the use of AI and others may allow you to use it to help explain concepts or frameworks as part of your preparation.   

Keep in mind that recruitment teams want you to be honest and authentic in your applications and it is difficult to achieve that if you use AI to draft your answers. In using AI tools, you risk sounding generic and uninteresting. Read our Use of AI in Job Applications & Assessments webpage for further guidance.

Watch the video from Jonathan Black, the Director of Careers,University of Oxford and former consultant with Booz Allen Hamilton, who shares his advice for tackling management consulting case studies.