The Best way to prepare for Mckinsey interview rounds (PEI + Case interviews)

Question

Hi there,

I got an invitation for the first round which will start at mid-October.

Any suggestions about books, references, coaching ?

Is the duration (1 month) sufficient to get prepared?

Thank you

Answer 1

Hey there,

McKinsey interviews are a bit different than other consulting firms' interviews

The case

Let's break it down below as well:

1. The difference between a McKinsey case and a non-McKinsey case first and foremost lies in the interviewer-led format as you are aware. Every case you have in this case book can be asked from an interviewer-led perspective.

In the McKinsey interview you will have to answer three different questions types - broadly speaking:

Structuring
Exhibit Interpretation
Math

While in candidate-led cases, they should arise naturally when you drill down into your structure, in McKinsey interviews, the interviewer will bring them up in succession.

2. The second big difference lies in the nature of questions asked at McKinsey. At the core, McKinsey wants to see creative ideas communicated in a structured manner, the more exhaustive the better.

As a result, McKinsey cases will usually be very creative in nature and not something that can be solved by looking at industry frameworks or industry trends. For a specific example, reach out as I have some materials on that.

Be aware that frameworks were applicable in the 2000 years, the era of Victor Cheng and Case in Point. McK has long caught up on this and the cases you will get during the interviews are tailored in a way to test your creativity and ability to generate insights, not remember specific frameworks.

3. The third big difference is how to answer the questions in a McKinsey interview. Since the interviewer guides you from question to question, you need to be in the driver's seat for each question and treat each almost like a mini case in itself.

Your goal should be to come up with a tailored and creative answer that fits the question. The framework should - broadly speaking - follow these three characteristics:

Broad
Deep
Insightful

The firm wants to see exhaustive and creative approaches to specific problems, which more often than not do not fit into the classic case interview frameworks (or can be derived from industry drivers and trends) that were en vogue 10 years ago...

Again, this only applies if everything you say

adds value to the problem analysis
is MECE
is well qualified
includes a detailed discussion of your hypotheses at the end

As a result, you can spend several minutes, guiding the interviewer through your structure!

Now for Structure and Exhibit Interpretation, there is also no right or wrong answer. Some answers are better than others because they are

deep
broad
insightful
hypothesis-driven
follow a strong communication (MECE, top-down, signposted)

That being said, there is no 100% that you can reach or the one-and-only solution/ answer. It is important that your answers display the characteristics specified above and are supported well with arguments.

As for Math questions, usually, there are answers which are correct (not always 100% the same since some candidates simplify or round differently - which is ok), and others that are wrong, either due to the

calculation approach
calculation itself

The difference in format and way of answering a question is the reason why I recommend preparing very differently for McK interviews vs. other consultancies.

Now that you know about

the different format
the different question types and case briefs
the ways to answer the questions

you can start using the cases you already have and approach them in a McKinsey-specific way.

If you have any more questions, please feel free to reach out for some free guidance on how to come up with your own McKinsey-type cases on the spot.

Also, check out this answer I wrote on how the cases McKinsey posts online are comparable to the actual interviews: https://www.preplounge.com/en/consulting-forum/are-mckinsey-website-practice-cases-representative-for-what-will-come-10002

For more details on the case, see here: https://www.preplounge.com/en/mckinsey-interview

The PEI

The McKinsey PEI (Personal Experience Interview) is one of the most talked-about features today in consulting applications. It differs significantly from the personal fit interview conducted at BCG, Bain, or any other consulting firm. While the content of the interview has not changed in many years, most candidates are still a bit lost when it comes to preparing for it.

If they try to research on Google, most results present myths or half-truths that unnerve them in the best case and have them prepare irrelevant answers to non-existing questions, missing the actual point of these interviews, in the worst case. Even here on the forum and on some coaching profiles, misinformation is spread about this interview…

I have created a PEI checklist to overcome this:

1. Learn about the PEI dimensions

Below are the three dimensions plus some ideas on what to include:

a. Entrepreneurial Drive

Set a goal for yourself and pursue it relentlessly against all odds
The focus here should be on overcoming obstacles, showing ambition and dedication as well as ingenuity

b. Personal Impact

Persuade a group or individual to adopt a certain idea or plan of yours
The focus should really be on the influencing tactics you used to reach your desired outcome

c. Inclusive leadership

Show that you can manage a diverse team, leading it to a successful outcome
The focus here should be on all traits that make a great leader (e.g., inclusiveness, mentor, mediator, go-to person, people person,...)

2. Select the right stories with the right content

When it comes to the selection of your McKinsey PEI stories, you need to think about three dimensions in the following order:

a. Fit with the actual dimension that is asked. The stories need to fit the criteria set out by McKinsey to match with Entrepreneurial Drive, Leadership, and Personal Impact. For content ideas see above.

b. Diversity of experience. Your stories should be from different walks of life, e.g., jobs or careers, universities, extracurriculars, etc. Don’t take all stories from one experience.

c. Recency. In general, the more recent the better. Unless you interview for an experienced hire or more senior position, your stories should not date back more than 2-3 years.

Make sure that

you draft two stories each to always have a backup story in case the interviewer rejects the first story
you are aware that the interviewer might interrupt you a lot to ask detailed questions, which means your stories need to go very deep as you should be ready to answer very focused questions such as ''what did you say at that moment?'', ''How did he react'', etc.
create catchy headlines for each story that already convey the main message
you create content for each story to be able to talk freely for around 10 minutes

3. Learn how to communicate them most effectively

Communication is key in the interview. Speak like a consultant, follow a logical, top-down structure, and make sure to

focus on yourself and your own role all the time
keep the context brief and really focus on your own actions (context 2 minutes, your actions 8 minutes)
practice your stories with peers and friends

4. Shortcut get it right quickly

Book a session with a coach that knows these dimensions inside out to make sure that

they contain the right content
they are communicated in the most McKinsey-like way
you can anticipate and prepare for the detailed drill-down questions the interviewers will ask

For more details on the PEI, see here: https://www.preplounge.com/mckinsey-pei

---------------------------------------------

Reach out for coaching or more McKinsey-specific help. I have a video program on how to prepare and ace those interviews.

Cheers,

Florian

Answer 2

Congratulations on being invited to interview!

There is no ‘set’ time that you need to prepare for an interview -that being said if case interviews don't come naturally to you then you will want to start sooner rather than later.

In terms of how to prepare:

1. PEI

There are three categories of PEI questions - leadership, personal impact (when have you done great things and how did you do them); and entrepreneurship
You want to develop at least 2 stories for each area and be prepared to talk about them in depth

2. Cases

You'll want to have a few high level frameworks in mind so that you can easily structure your answers - Case in Point is a good book to give you a few high level ones. That being said it's a bit convoluted - I can share some simpler ones that I've used if that'd be helpful.
However, don't get stuck on frameworks! You need to be able to answer the questions without giving a generic answer. The McKinsey website is a good place to go for a few high level practice questions.
You need to be able to do basic mental maths - 12 times tables, be comfortable multiplying and dividing big numbers (e.g., lots of 00s), know how to calculate percentages
You then want to practice a few cases. You can link up with other candidates here to do that; or for more targeted and experienced feedback hiring a coach can be really helpful (obviously I'd say that, I'm biased, but I think it is!)

There are many other tips and tricks but I won't make this answer any longer - let me know if I can help at all. And good luck!

Answer 3

Hello there, congratulations to making it to the interviews!

It is difficult to comment on your chances without knowing where you are starting from. So I do recommend that you do a mock interview with an experienced coach who can tell you what to focus on and comment on whether 1 month is sufficient.

If you are starting completely from scratch, it probably won't be enough. I would ask to postpone the interview by a further month and focus on:

1. Nailing your fit stories – really understanding what the McKinsey is looking for per fit dimension (Leadership, Entrepreneurship, Personal Impact), preparing 2 stories per dimension and polishing them to perfection: using the STAR or PARADE technique, presenting them to a friend or a coach, recording yourself on camera…

2. Learning the framework and practicing cases. The important thing is to establish and keep a case-solving routine with case coaches and/or case partners (e.g., other candidates to consulting). I really recommend including at least some sessions with the ex-McKinsey interviewers in that routine: they can help you understand exactly what the interviewers will be looking for. In addition, I recommend filling in a matrix you can see below to ensure reasonable coverage of industries x types of case by your interview date.

Good luck to you, feel free to reach out for more tips on how to ace your interviews!

Answer 4

Hi there,

1) Any suggestions about books, references, coaching?

You can find a few tips here:

▶ 4 Ways McKinsey Interviews are Different

▶ 3 PEI Dimensions You Should Know

▶ McKinsey Final Round Tips

In terms of the PEI: please note that McKinsey is piloting a new PEI dimension (Embracing Change) besides the usual ones (Inclusive Leadership, Entrepreneurial Drive, Personal Impact).

I am fully booked before your interview, but if you need help please feel free to PM me, happy to direct you to a few resources which I believe are good.

2) Is the duration (1 month) sufficient to get prepared?

Totally depends on

How much time per day you can prepare
Your current level
The resources you can use

Assuming you can leverage good resources and can put at least 40-50h of prep starting from zero (may be less if you are already advanced), this could be enough.

If you have doubts, it is totally fine to ask to reschedule. There is no penalty if you ask – worst case they will say it is not possible.

Good luck!

Francesco

Answer 5

Hi there,

Read this article on case prep: https://www.preplounge.com/en/articles/how-to-shift-your-mindset-to-ace-the-case

Read this article on fit prep:

https://www.preplounge.com/en/articles/tell-me-about-yourself-interview-question

I recommend the following steps:

1) An initial planning session with a coach: 1 hour with a coach now will have a productivity multiplier effect on all your efforts moving forward. They will figure out what materials are best for you, guide you towards the best ways to learn, and come up with a preparation plan with you.

2) Leverage free resources first: PrepLounge Q&A and case library, Poets and Quants, SpencerTom, Google, etc.). Leverage these options, read-up, and over time you'll get a feel for what you really need and where you really need to invest your hard-earned $

3) Case with other PrepLoungers: Casing with other PrepLoungers is free. Not only do you get to practice casing, but you get direct feedback. Additionally, you learn a lot just from casing others. Finally, from other PrepLoungers you'll learn which materials/coaches are helpful.

In summary, while free options don't beat paid options, you can use them for a while to get a feel for what works for you. Have an initial coaching session to get you on the right track, then go the paid route when it's clear either 1) You are stuck or 2) It's clear the paid route will improve your productivity/progress