You cannot wing your way into a job at a top strategy consulting firm.

What is the Case Interview

Consultants essentially solve business problems for clients. In a case interview, you will be asked to solve a business problem for a hypothetical client in between 25-45 minutes. These cases tend to be based on interviewers’ real case experiences. There is generally no right or wrong final answer; the interview is testing your core casing skills. These skills are structured thinking, good communication, fast and accurate mental maths, business acumen and creativity.

Example Case

A fast-food chain based in the US has been unprofitable in the last 2 years. The CEO has asked your consulting company to figure out why this is the case and come up with ideas to increase profits. You will begin by asking some clarifying questions e.g. by how much would the CEO like to increase profits and by when. You will then create a framework that helps you tackle this problem. This framework should indicate structured thinking and creativity. For example, here, you may break this problem down into two main buckets - revenues and costs. Within the revenues bucket, you may choose to split revenues by products, and compare the revenues of your client to its competitors. On the costs side, you may split this down into fixed and variable costs, and specify each of the costs that a fast-food chain specifically may face. You would then suggest some sort of hypothesis for where you want to start e.g. ‘I think that a decrease in revenue may be the driver of this fall in profitability. Do we have any information on our client’s revenues over the last 3 years alongside its competitors’ revenues?’ A consultant cannot research and analyse every potential relevant factor. They charge by the hour and that would be very expensive. You must learn to prioritise and use the 80-20 principle. The interviewer is likely to give you some data at this point or point you towards a different part of your framework if they think that another area is worth beginning with. With data, your interviewer is testing three things: your ability to perform mental maths and your business acumen tested through your ability to draw key insights. After this, you may have reached a sufficient hypothesis for why the business is unprofitable, or you may require more information. If so, ask for it. You may then brainstorm ways in which the firm could boost profits over the next 3 years, addressing the 2nd part of the prompt. Here you should try and structure your brainstorming, think creatively, and communicate your ideas well. Finally, you are likely to have to present a recommendation for the client. Here you should summarise your findings and communicate in a top-down manner.

General Advice

Once your CV is great and you’ve smashed whatever tests the company has thrown at you, your achievements and background no longer matter (outside of fit interviews); all that is important is how well you case.

Here are some very important pointers I picked up on:

1. Do not learn the kind of frameworks you might find in books or on the internet. Practice building your own frameworks.
2. Read a casing book e.g. Victor Cheng or Marc Cosentino, but only skim through them so that you get a sense of the key takeaways but don’t become robotic.
3. Make a preplounge account. Get the premium version. Do lots of live cases with strangers.
4. I would recommend practising 15-20 live cases over 3 months i.e. 1-2 cases a week. Ensure that between cases you are actively trying to take on board feedback from your previous case by doing drills. For example, if you received feedback that your framework was not very comprehensive, find a casebook, read a prompt, and just draw out a framework for that case by yourself. Repeat this until your frameworks seem to be getting better. You don’t need to go through the entire case; just drill the parts that you are weaker at.
5. When you find a good casing partner, keep hold of them. Find someone who you can learn from, and that gives you good, comprehensive feedback. Set up regular casing sessions with them.
6. After every few cases, try to find ways to improve your overall approach to casing. Go back and read new websites, or look at the tips in case books. Often someone will suggest a way in which you could tackle recommendations or mathematical questions that is better than how you are currently doing it.
7. Practice your mental maths. Even if you have a degree in maths, this is worth doing. Practice long multiplication with lots of 0’s under time pressure, and learn basic consulting formulas e.g. breakeven, payback period, profit etc. There are lots of sites where you can do this e.g. zetamac, managementconsulted, and casecoach.
8. Get a casecoach subscription. It is worth it for the drills and particularly if you have any written/ presentation cases. My Strategy& structured case studies were in the same format as the practice cases on the casecoach site. You can also use Crafting Cases for drilling.
9. Try to case with a current/ex consultant at least once. Bain partnered me up with a current associate consultant once I received an interview invite, and we did 2 practice cases over weekends. The feedback that you get from 1 practice case with a current/ex consultant is equivalent to 5 practice cases on preplounge.
10. Watch videos of people casing. I found this video by Bain incredibly useful. If you are a member of SEO, go to your portal and watch the Step into Consulting videos. These are all led by great casers at MBBs, and the advice is invaluable.
11. Don’t overdo it and burn out. I tried not to case or think about casing for at least 1-2 days before an interview. Do lots of activities to take your mind off things - go to the gym, meditate, do yoga, go for dinners, and go to the cinema. Get a good night’s sleep for 2 days before your interview.