The best way to prep for a case interview. (10 Tips)

Your knowledge and character will be put to the test

Recruiters will push you to your limits, put you into unconventional situations and force you to think on your feet. After all, you are a candidate for working with some of the best brains in the industry. You will be tested in multiple interviews, with the smallest details making the difference between advancing to the next round and being ousted.

How do I keep my cool and not crack under the pressure? What framework is best suited to structure my thoughts for this particular case?

The tips contained here are compiled by our most experienced consultants and will bring you closer to a job in consulting. However, before delving into this area, it is important to understand the nature and fundamental components of what a case interview is and why they are conducted.

Case Interviews: What you need to know

First and foremost, consultancies utilize case interviews with the intention of probing the quantitative and qualitative skills of an applicant. The way you present yourself and apply the limited amount of information given to you will also be analyzed as these represent crucial qualities of any aspiring consultant. The reason for the prevalence of the case interview format is that the topics and themes handled in most cases reflect conditions close to the reality of the day-to-day activities of a consultancy. It requires the applicant to ask the right questions, apply structured frameworks and think out-of-the-box.

A case interview may take up to an hour. During the entire application process you will partake in up to six case interviews in two rounds or more. This is dependent on the position you are applying for.

What challenges await you

Most case interviews have the same underlying structure. After an initial, light conversation in which the interviewer will evaluate how good the personal fit between you and the company is, you will be presented with the case question. You will have time to solve the question and will subsequently need to present your findings. This part of the interview is intended to be more of a dialogue. You will need to be proactive and ask questions when attempting to close in on the correct conclusion. Often times the consultant will attempt to guide you into the correct territory by asking questions himself.

Apart from this style of interview, a case can be interviewer-led or candidate-led. Our BootCampdeals extensively with the differences between interview-led cases and candidate-led cases. The three core types of cases you will be confronted with are business casesestimating cases and brain teasers. All three types of cases will require a sophisticated approach and a thorough analysis.

The different case types

A business case usually revolves around the estimation of a company’s profitability and investment opportunities. It portraits a business problem that requires solving. Estimation cases (also known as market sizing cases) pose a similar challenge. Here you will need to evaluate the potential and profitability of a certain market or a specific product. Brain teasers are usually a riddle which will need an out-of-the-box approach to solve. However: It’s important to not get hung up too much on the frame of the interview. Which brings us to our first suggestion:

Case Interview Tips

  1. Focus on the task at hand.
  2. Ask the right questions.
  3. Buy time with repetitions.
  4. Only form a hypothesis with sufficient information.
  5. Utilize data for your analysis.
  6. Take clear notes.
  7. Sometimes there is no clear answer.
  8. Bring your mental math up to speed.
  9. Practice makes perfect.
  10. When in doubt, reschedule.

Tip 1: Focus on the task at hand

Don’t think too much about the approach your interviewer is taking. It should not matter if the conversation is interviewer or candidate-led. If you go into your interview with a profound understanding on how to handle even a difficult case, the format of the interview shouldn’t be an issue. Keep a cool head and structure your thoughts.

Tip 2: Ask the right questions

Ask your interviewer questions in order to clarify the case. This is expected behavior. Make sure you understand what the business model and your objective in the respective case is (regarding both money and the timeline). If there are any other possible limitations you are unsure about, ask your interviewer in a concise away. Asking unnecessary questions will raise doubts about your ability to work efficiently under pressure.

Tip 3: Buy time with repetitions

A common trick consultants use is the repeating of facts or overall goals. By doing this you’re showing a fundamental comprehension of the case and emitting an aura of control, gradually heading towards a solution. This technique can give you more time to think. Articulating the facts of the case can also be a source of clarity and allow you to more quickly form solutions.

Tip 4: Only form a hypothesis with sufficient information

Do not state a hypothesis at the beginning, a stage in which you may still have incomplete information. Get a good sense of the case’s environment and ask sensible follow-up questions. Only then should you frame a structure and formulate a hypothesis.

Tip 5: Utilize data for your analysis

Taking wild guesses is a death sentence for you case interview. Make sure your claims are backed up by the facts and remain calm when presented with new information. Consultancies will closely observe how you make use of new data and incorporate it into your hypothesis.

Tip 6: Take clear notes

Taking structured notes is a highly underrated skill when dealing with a case. Making sure your notes are coherent and clear will make your thoughts easy to navigate and ensure you don’t lose your footing during the interview. Place your sheet horizontally in order to maximize your space and jot down the key question of the case. This way you will never lose sight of the case’s main objective.

Tip 7: Sometimes there is no clear answer

In many cases a case interview has no “correct” or “standard” answer. The case may encompass you exploring the issues and walking down several paths. There are often many solutions to a single case which may differ from the interviewer’s expectations. In the end, what counts is your train of a thought and how you got to your solution.

Tip 8: Bring your mental math up to speed

Break down complex math problems into multiple smaller operations. For example:

97 x 53

= (100 – 3) x (50 + 3)

= 5000 + 300 – 150 – 9

= 5141

Knowing the shortcuts for a wide range of calculations will greatly simplify math problems. Make use of our mental math tool in order to practice your efficiency. This will greatly ease the pressure if confronted with a math problem in your interview.

Tip 9: Practice makes perfect

There is simply no way around it. You will need to invest a vast amount of time into preparation. Convincingly acing your case interview is no easy feat. In total you should prepare for well over 50 hours in an up to 6 week time period. Be sure to practice mental math and market sizing on a daily basis. Though this can be fatiguing at first, you will notice that gradually improving your performance will motivate and make you thirsty for more.

Practicing a variety of cases is paramount in your preparation. Take a look at our vast case library with which you’ll be prepared for all possible case types. Our case collection includes cases which have been used in case interviews in the past.

Tip 10: When in doubt, reschedule

If you’re not feeling confident about your chances, don’t hesitate to reschedule. If you take this course of action, take a few things into consideration. Make sure to suggest an alternative day and avoid rescheduling multiple times at all costs. The consultancy will be grateful for you suggesting an immediate alternative. Try to be transparent as to why you are rescheduling without going too deeply into details. However, rescheduling should only be used as a last resort.