McKinsey Case Interview Preparation: the only post you'll need to read April 18 2016

McKinsey interviews are among the hardest job interviews you will come across. The questions are difficult and specific to McKinsey and the interviewer can also sometimes seem intimidating.

But the good news is that with the right preparation it can actually become relatively straightforward to succeed at a McKinsey interview. We have put together the ultimate list of facts and tips you need to know to maximize your chances of success.

1. One in ten interview candidates get a job offer

First, it is important that you understand the different stages of your interview process with McKinsey and your chances at each step. In most countries, McKinsey uses four filters to select candidates:

  • CV and cover letter screening
  • McKinsey Problem Solving Test (PST)
  • First round of interviews
  • Second round of interviews

In a recent interview, Dominic Barton, McKinsey’s Global Managing Director, revealed that about 1% of the 200,000 candidates applying to the firm every year receive a job offer.

Assuming a 33% success rate at the four steps of the recruiting process described above, we estimate that McKinsey interviews about 21,000 candidates every year and that they extend a job offer to about 2,200 of them. If you have been invited to a first round interview with McKinsey you therefore have a 10% chance of getting an offer.

  • Filter 1 / CV and cover letter: 200,000 candidates
  • Filter 2 / McKinsey PST: ~65,000 candidates
  • Filter 3 / First round of interviews: ~21,000 candidates
  • Filter 4 / Second round of interviews: ~6,800 candidates
  • Job offers: 2,200 candidates

The good news is that the first and second round interviews are really manageable when you know what to prepare for. The first thing to focus on is really trying to understand what skills McKinsey is testing for in case interviews.

2. Skills tested by McKinsey case interviews

McKinsey uses case interviews to test three types of skills that are used by consultants in their daily job:

  • Problem structuring and maths skills
  • Creativity and business sense skills
  • Communication skills

First, McKinsey already started testing your maths skills with its Problem Solving Test. This skill will continue being tested during case interviews and you will be expected to perform mental maths both quickly and accurately. In addition, your interviewer will also ask you to solve the problem at hand in a structured way. In simple terms, that means you will be expected to solve the questions you are asked in a clear step-by-step approach that is easily understandable by your interviewer.

Second, McKinsey case interviews are designed to evaluate your business sense and creativity. That means your interviewer will assess your ability to come up with a range of ideas that make business sense to solve the client issue at hand. For instance, you could be asked to find innovative ideas for a restaurant to grow sales, or to decrease costs.

An important nuance is that interviewers will not assess your business knowledge per se. In other words, you are not expected to have any knowledge of the industry your case will be about. For instance, you could get a case about re-insurance and not know what the re-insurance industry is. This is perfectly normal. In these situations, your interviewer will expect you to ask questions about the industry and will help you understand its specificities.

The only expectation is that you know basic business concepts such as revenues, fixed and variable costs, etc. We have summarized the finance concepts you need to know for consulting interviews here.

Finally, your interviewer will also test your softer skills. This includes how you communicate your ideas and interact with others. Good soft skills are critical to deal with clients as a consultant and a lot of interviewees underestimate their importance. To put things simply, you should try to communicate your ideas in as a structured way as possible during case interviews and behave in a professional way.

Take a look at the following excerpt of one of our McKinsey live case interview videos to find out what a good, consistent approach to answering case interview questions sounds like.

 

3. Differences between 1st and 2nd round interviews

The second important thing to understand is the number of case interviews you will have and how they will differ. In most cases, you will have two rounds of interviews. The number of interviews by round may vary but it is usually between 2 and 4. In total, you will therefore have between 4 and 8 interviews before getting a McKinsey job offer.

First and second round interviews are similar in format and difficulty. However, your first round interviewers will usually be more junior than your second round ones. Associates (2+ years of experience) or Engagement Managers (4+ years of experience) usually lead first round interviews while the second round is led by Partners (10+ years of experience).

In theory, McKinsey takes into account your performance at both first and second round interviews when it makes the decision to make you an offer. However, in practice, your performance during the second round carries a bigger weight simply because Partners will have a stronger voice when the recruiting group will get together to make a final decision on your application. It is therefore particularly important that you do well at your second round interviews.

Let’s now look at how interviews are structured and help you prepare for each of the different sections. Your interviews will usually last between 45 and 60 minutes and consist of two parts: 

  • Personal Experience Interview – for 25% of the interview time
  • Case Interview – for 75% of the interview time

Let’s first focus on personal experience interviews.

    4. Personal Experience Interview

      The PEI part of your interview will last about ten minutes. It is fairly different from a typical “CV interview” mainly because your interviewer will only assess you on a single topic. Interviewers at other firms tend to cover a large range of topics during a “CV interview” but that is not the case at McKinsey.

      The good news is that the topics on which you will be assessed are very predictable. They are made relatively clear on McKinsey’s career website: personal impact, leadership abilities, entrepreneurial drive and problem solving skills. For instance you could be asked: “Tell me about a time when you led a group of people through a difficult situation” or “Tell me about a time when you had to solve an extremely difficult problem”. 

      Our recommended approach to prepare for these questions is to craft a story for each of the four skills McKinsey will test you on. You can then use and adapt these stories depending on the exact question your interviewer will ask. There are different structures you could use to tell your story but we recommend keeping it relatively simple:

      • Context: start by giving the necessary context on the example you are using
      • Problem: outline the problem you and your team were facing
      • Solution: explain the solution you came up with to solve the problem outlined
      • Impact: if possible, quantify the impact you had in solving the problem
      • Lessons: finish by any lessons you might have learned in the process

      There are two common mistakes candidates make when answering McKinsey PEI questions. First, a lot of candidates spend too much time on setting the context when telling their story. Second, some candidates forget that the question is about them. They should therefore focus on what they did, what their impact was on the situation they are telling their interviewer about. When you craft your four stories you should keep these common pitfalls in mind and try to avoid them.

      For more details and example answers, you should read the following blog post on how to impress your interviewer when answering Personal Experience Interview questions.

      5. McKinsey case interview structure

      After the PEI question, your interviewer will then move on to the case interview.

      In this part of the interview, you will be presented with a business case about a company facing an issue. For instance, your case could focus on an industrial facility facing a profit challenge, or a company that needs help to make a strategic decision on a new product. Cases are usually a simplified version of real projects your interviewer worked on in the past.

      Your interviewer will tell you about the situation the company is facing and will ask you questions about the situation. She may also provide you with documents such as graphs and tables with figures about the company. You will be allowed to use scrap paper to structure your thoughts and perform calculations. However, you will not be allowed to use a calculator.

      Most McKinsey case interviews use the following structure:

      • Situation
      • Framework question
      • Quantitative question
      • Creativity question
      • Recommendation

      First, your interviewer will introduce you to the company’s situation and the business problem they are facing. Then, the interviewer will ask you to identify the areas you would look at to solve the problem at hand - this is the framework question. You will then be asked to solve one or several quantitative questions that will help further investigate the problem faced by the company and draw some initial conclusions.

      In addition, at some point during your interview, you will be asked a creativity question. These are usually open-ended question such as “what are the other areas the company could look at to increase its online sales?”. Finally, at the end of the case, your interviewer will ask you to make an overall recommendation for the company based on the analysis you have just carried out.

      Although the format and order of questions may vary from one case to the next, you will almost invariably come across these types of questions during your McKinsey interviews and should therefore prepare for them. To find out more about the format of case interviews, you can download our Free McKinsey Case Prep product here.

      6. Differences between McKinsey and other cases

      All consulting firms use case interviews during their recruiting process. But McKinsey interviews are different in two regards.

      First, McKinsey interviewers tend to control the pace of the interview much more than other interviewers. They’ve got a list of questions about the case they want to go through with you and will take you from one question to the next. If they feel you spend too much time on one question, they might interrupt you and ask the following question. Some people call this “interviewer-led”case interviews. At other firms such as Bain or BCG, interviewers give you more control over the pace of the interview. Some people call this “interviewee-led” case interviews. The skills tested in both types of cases are the same but you should expect slightly different behaviours from your interviewers.

      Second, there is a lot of competition to get into McKinsey, and your interviewer will probably challenge the quality and logic of your answers more than at other firms. That being said, interviewers are instructed to always be well intentioned and therefore will not try to “trip you up” or misguide you.

      Let’s now walk through the skills you need to develop to be able to impress at these difficult case interviews.

      7. Develop confident maths skills

      It is almost impossible to crack case interviews without being able to perform maths calculations quickly and accurately. This is because every case interview at McKinsey includes quantitative questions and you will not be allowed to use a calculator to answer questions.

      When you start preparing for case interviews, it is common to have relatively rusty maths skills. However, in our experience, successful candidates take the time to refresh their memories and learn a few maths shortcuts at the start of their preparation. This initial time investment provides them with the confidence they need to perform calculations confidently in case interviews.

      We definitely encourage you to make this initial time investment. In fact, this maths preparation is the first step of the McKinsey Case Interview Training Programme we have put together. To help you refresh your maths skills, here are also a few maths shortcuts you should consider using. 

      8. Acquire a consistent answering method for each type of questions

      As mentioned previously, McKinsey case interviews follow a pre-defined set of questions: situation, framework, quantitative, creativity and recommendation questions. It is therefore critical that you learn to quickly recognise these types of questions and that you develop a consistent method of answering them. Approaching each question with a pre-defined method will enable you to build strong habits. On the day of your case interview, these habits will make a huge difference as they will reduce your stress and save you a lot of time and mistakes.

      At IGotAnOffer, when we were preparing for case interviews, we were frustrated by the lack of consistent method that existed to crack case interviews. We have therefore developed a method to consistently answer McKinsey case interview questions. After being successful at case interviews, we then set out to share this “IGotAnOffer” method with future generations of candidates through our McKinsey case interview programme.

      Having a consistent method to answer different case interview questions may feel a little mechanical at first. But trust us, if you stick to a pre-defined method you will experience a step-change in your performance that will help you get a job offer at McKinsey.

      9. Practice out loud

      Another key element to succeed at case interviews is practicing in real conditions. If you can practice case interviews with a partner you should definitely do so, that will help you progress faster.

      However, when you practice by yourself there still is something you can do to recreate case interview conditions: practicing out loud. While this may sound a little awkward at first, in our experience, candidates who have forced themselves to use this technique have progressed much faster than others.

      When you practice out loud, you should both play the role of the interviewer and the interviewee. You should ask yourself the questions your interviewer would ask you and then answer these questions out loud as if you were in the interview.

      The reason this technique works so well is that it forces you to practice communicating your answer to your interviewer. As mentioned previously, communicating in a structured and simple way is a key skill assessed by McKinsey. Developing this skill as much as possible will make a big difference on the day of the interview.

      10. Learn from every case

      Finally, the best candidates learn as many things as possible from every case they do. In our experience, it is much better to train on 20 case interviews and to learn a lot from them than to train on 40 and not learn much. 

      To ensure you make the most of each case you practice on, we recommend that at the end of each case, you write down what you have learned as well as the main mistakes you have made. After a few days you should then do the case again. This approach will enable you to make sure that you apply what you have learned and to ensure you are making progress.

      Ready to start training? You can visit our McKinsey Case Interview Training Programme page to learn more about how to get a job offer at McKinsey. 

      Once you have taken McKinsey Case Interviews

      Once you have taken McKinsey Case Interviews, feel free to leave a comment at the bottom this page to talk about your experience. It will be extremely valuable to future candidates!

      Good luck!

      Additional resources 

      Candidates from the best universities around the world use our McKinsey Case Interview Training ProgrammeFree McKinsey Case Interview PrepMcKinsey PST Training ProgrammeFree McKinsey PSTBCG Potential Test Training Programme and Free BCG Potential Test. Some races are worth the extra effort - let's get started!

      The IGotAnOffer team

      Photo: Ed Gregory / Stokpic