How Long Does it Take to Prepare for Case Interviews?

Preparing for case interviews is a time-consuming process… but how time-consuming, exactly – and why? What if I have only one day to prepare everything – is there any chance that I will pass the case interview?

In this article, I will be answering all of these questions, with 6 last-minute tips that are useful even for those with one day left to prepare!

How long does it take to prepare for case interviews?

With intensive training, case interviews take around two to three months to prepare. This is rather time-consuming because case interviews are difficult – they test a wide range of skills that can only be improved with time, namely analytical problem-solving, behavioral/social skills, practicality, etc.

Of course, preparation time varies depending on each person. I’ve had customers who prepared in less than a week – but that’s more the exception than the norm. In all cases, to be fully prepared for case interviews, you should have done everything on the list below:

Step 1: Mastered the basics of case interview theory

Step 2: Practiced cases that match your level

Step 3: Sharpened your business intuition

Step 4: Mastered consulting math

Step 5: Practiced at least 10 mock case interviews


Six instant tips to crack case interviews

Now, is there any chance of passing the case interview even if you don’t have enough time to tick even one of all those boxes above? Actually, there is. The answer lies in a few “quick and dirty” tips, which I’ll share with you in a moment.

Imagine a case interview just falls out of the sky and into your lap, scheduled for tomorrow – how can you even prepare?

I am a firm believer in the 80-20 rule – which states that 20% of the causes lead to 80% of the consequences. 

In the case interview prep context, 20% of your learning efforts will bring about 80% of the improvements – so the key to instantly and dramatically improving your case performance is to identify and focus on that 20%.

Below are 8 killer tips and tricks that helped me land a McKinsey offer, which was only previously available in the premium End-to-End Secrets Program.

Tip #1: Deliver a perfect case opening

The result of a case interview is determined the first 3 minutes. This is the 20% to focus on – if you nail the opening, you’ll make a better impression than most candidates; it’s also easier to perform well in 3 minutes than in 30 minutes, especially when the case hasn’t gotten tricky.

Additionally, you can prepare the opening in a formulaic manner – essentially learning by heart until it becomes natural. I’ve summarized 7 steps of the perfect case opening in the video below:

Tip #2: Be structured throughout the case

In case interviews, being structured with whatever you say is more important than giving solutions to the case! Yet, the high stress and a large amount of information in case interviews make it easy for even the brightest candidates to derail from the objective or present in an unstructured manner.

So how do you stay structured in case interviews?

To stay consistently structured in case interviews, you should:

  • Pause regularly to explicitly check where you are, and where you’re doing next. I call this the “map habit” because it is similar to using a map while traveling – pausing every once in a while to check your location, destination, and direction. 
  • Number the points/ insights that you’re going to say. Begin your speeches with this sentence: “There are X items that I’m going to say; they are: No.1 … No.2 … No.3 …”. This is an easy and effective way to make your pitches sound instantly structured. 

Tip #3: Take good notes

Even the smartest candidates make silly mistakes in case interviews – forgetting data, messing up the numbers, getting stuck with frameworks, etc. Looking back at hundreds of coaching sessions I did, I found one thing in common – none of those candidates could take good notes.

So how do you take good notes in case interviews?

To take good notes (meaning, to keep them MECE and organized), separate your paper sheets into 3 groups: data sheets, presentation sheets, and scratch sheets, in which: 

  • Datasheets store and process every piece of incoming data
  • Presentation sheets develop and present any “outgoing” contents
  • Scratch sheets exist to keep other sheets clean

Tip #4: How to ask for data

Data is the fuel for the case interview engine. Without it, your analysis can’t progress. The problem is that interviewers don’t simply give out precious data for free. Data has to be earned.

To ask for data, you must convince the interviewer of the need to supply you with more information, in the following 4 steps:

Step 1: Create a good impression

Step 2: Explain the purpose of the data

Step 3: Explain the method of acquiring that data

Step 4: Ask open-ended questions

Tip #5: Make the final pitch short

Your final solution pitch must be short, to-the-point, action-oriented, and client-friendly.

Imagine you’re in the elevator with the client CEO (or in the example case, the Chief Captain) and he asks for your findings – you should be able to deliver it before the elevator arrives at its destination floor! This is a “question” they ask at the end of a case interview.

The pitch should always begin with the root causes, immediately followed by your recommendations – client CEOs don’t have much time to waste on the procedure, so no need to bring it up – and lastly, end your pitch in a client-friendly fashion, saying “We’d be happy to work with you to implement the solutions”. Voila, you’ve nailed that pitch!

Tip #6: Develop your personal scripts

Every tip I’ve mentioned above is for recurring situations in case interviews, and they can be dealt with using formulaic responses. This means you – as a candidate – can make personal scripts and learn them by heart until they all become your second nature.

This approach has proven successful with all of my coachees, and it’s also a major part of our Case Interview End-to-End Secrets Program. You will find my own personal script I used back in the day, and I will also personally give feedback to the scripts of members of the program.

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