L.E.K. Case Interview 2024: Format, Criteria & Examples

According to Vault, L.E.K. Consulting is one of the top prestigious consulting firms. L.E.K. is a Tier 2 consulting firm (just after MBB consulting firms!) - considerably desirable yet quite challenging to get in L.E.K. employs case interviews as part of their recruitment process for consultants.

Let’s have an overview of the L.E.K. case interview: when to take the interview, assessment criteria, interview format, question example, how to pitch, and how to prepare for the case interview in this article.


What is L.E.K. case interview?

L.E.K case interview is the last test to become an L.E.K consultant

The L.E.K. case interview is the screening interview of L.E.K. Consulting, where candidates must solve business problems (or cases). The interview evaluates whether candidates possess the capabilities and qualities to become an L.E.K. consultant.

L.E.K. case interviews are candidate-led, requiring the candidate to lead and manage every step of the case-solving process, including structuring the issue, developing frameworks, requesting data, synthesizing findings, and providing solutions. The interviewer just presents the topic, instead of asking questions concerning the case.

Before getting to the case interview, you must pass the initial screening rounds, which include resume screening and aptitude test.

In the resume round, you’ll of course need a consulting resume, just like what you’d need for McKinsey, and a cover letter, then submit it on L.E.K.’s website.

The aptitude test concerns numerical, verbal, and logical reasoning questions, some offices might even use SHL assessments. It’s quite similar to McKinsey’s problem solving test before it was retired and replaced by the problem solving game. 

There are 2 rounds in the case interview process

The first round (online round) includes a few minutes of fit questions to check candidates’ experience and alignment with the position and two 30-minute cases, one quantitative (something like market-sizing) and one qualitative (like finding a solution). 

Round two will also have a few minutes of fit questions, but now three face-to-face interviews, two oral cases and one written case. 

The oral cases are just like any case interviews from other consulting firms. They’ll usually take 30-45 minutes.

The written case is used by L.E.K. to simulate the actual work of a consultant, in which they need to visually plot out data and insights. It’s quite similar to the oral case, only you’re writing out your thought process instead of speaking it out.

The flow of the written case interview includes 4 stages:

  •  Receive the case: You receive the materials and the case questions from the interviewer.
  • Prepare for the pitch: You filter and analyze the data to extract the insights, then develop a hypothesis with backup evidence. You also need to prepare for the slides with essential insights.
  • Present the pitch: You present the slides and all the hypotheses & evidence with recommendations to the interviewer.
  • Have a follow-up Q&A with the interviewer: The interviewer will ask questions regarding your insights and hypotheses to ensure your understanding of the case and analysis of the details.

L.E.K. looks for those with achieving & analytical mindset

Just like all management consulting firms, L.E.K. looks for those who want to make an impact. The main value L.E.K. will look for are:

  • Outstanding academic achievement: Your GPA and school prestige. Your best bet? 4.0 at Harvard! But jokes aside, a 3.6 GPA should be good. Below that? Try to make focus points in other parts of your resume. This article might help!

  • Analytical ability: The ability to create a thorough, data-driven, insightful analysis and define the root cause and solutions to difficult problems. You show this in the case interview via constructing issue trees, answer guesstimate questions, etc.

  • Demonstrated leadership: The ability to inspire and motivate others. Consultants won’t simply look for “leaders” who just tell their subordinates what to do, but a guiding beacon, even for their superiors (very much like telling your boss what to do, but, think of it as inspiring ideas to them).

  • Collaborative approach: The ability to exchange facts and insights and effectively interact with people from various backgrounds and cultures. You’ll meet people hailing from mathematics, engineering, accounting, psychology, so play your collab cards right

  • Intellectual curiosity: The ability to actively and continuously seek and expand knowledge. To do this, start reading sơm business papers, and make sure you can absorb them 

L.E.K. case interview example

L.E.K. provides a short introductory page about their interview process, which contains several case interview question samples. You can check it out at the L.E.K. interview preparation guide. However, there is no explanation or answer key for the sample questions.

Still, L.E.K.’s case interviews are quite similar to Bain and BCG’s, so feel free to check out other candidate-led case interview samples here:

Also, here’s an article on case interview questions if you want to know more about common question types. And check out another article on market-sizing & guesstimate questions, which are quite popular in L.E.K.’s interviews.


How to prepare for L.E.K. case interview

Careful preparation is a must to ace L.E.K.’s case. You can tackle each aspect of the interview step by step.

Start from getting used to candidate-led cases and written cases, then further out with business intuition, consulting math, fundamentals & frameworks of case interview, then finally conduct mock interviews.

Step 1: Get used to the candidate-led case and written case interview

Examine examples of candidate-led case interviews to familiarize yourself with the case flow and how to interact with the interviewer.

You can also get familiar with more case interview samples and all instantly-effective tricks for case interviews with our Case Interview E2E Secret Program. Also, here’s our free video of a case interview example with an explanation and expert comments.

Step 2: Develop business intuition

Having business intuition significantly improves your performance in case interviews. Working on intuition is a gradual process that takes practice every day. You can improve your business intuition in two ways:

  • Written sources: Read business papers daily (Bloomberg is recommended). You can also find articles on McKinsey, Bain, and BCG’s websites. But be careful! The important thing is not your page count, but what you absorbed from them

  • First-hand experience and observations: Don't just do things like a machine; find out what the seniors are doing, why they did what they did, and how it has affected the organization. Everything is a learning process, and it’s up to you to squeeze out every bit of knowledge and experience

Step 3: Practice consulting math

L.E.K. will truly put your mental math ability to the test. This is an essential skill since L.E.K. consultants deal with massive amounts of quantitative data. To improve your math, you can:

  • Train your head: Apply mental calculations on any daily occasion unless an EXACT answer is required

  • Start small: Use a piece of scratch paper, give yourself some margins of error (5% is a good start); once you get used to it, remove the paper and narrow down the margin of error.

  • Establish a routine: Spare time for daily practice and get better each day, just like exercise. You’ll never notice the little changes, but they stack up HARD, and when you realize it, you’re probably doing math thrice as fast

Step 4: Learn the fundamentals and frameworks of case interview

L.E.K case interviews (or any other case interview) are based on the fundamentals - using hypotheses and issue trees, the MECE principle, and the frameworks. So, knowing them is extremely important and you should practice the fundamentals until you are comfortable.

A common mistake candidates make during their case interviews is to go straight for the frameworks. Frameworks require extensive adaptation to match actual cases. To customize appropriately, you must understand the fundamental knowledge first.

To know more about case interviews, here’s a dedicated article.

Step 5: Conduct mock case interview

Mock interviews are a great way to simulate the actual case interview session. You should examine your cases in great depth during the mock case interview. Record your session, replay, note the comments, and look for ways to improve.

Find a former consultant to help you with your practice - they are the ideal people; they've been there, they’ll know what a candidate must be. Through their feedback, you can improve on what needs to be improved and boost your chance of getting an offer.

We can also help you connect with consulting coaches (all former consultants!) for a more personalized feedback. Book your mock case interview session with us now!

And don’t forget the fit questions

Fit interviews are not the official round in the L.E.K interview process. Questions are integrated within each case interview. Here are example questions in the L.E.K. fit and behavioral interview.


Example question

Fit interview

Why are you interested in L.E.K?

Why are you interested in consulting?

What attributes would you bring to a case team?

What aspects of your internship did you like less?

Behavioral/Personality question

What experience are you most proud of?

What experience do you wish you could do over, and how would you do it differently?

What is a difficult decision you have made in the last year?

Describe a role where you changed the direction of a team, how did you do it?

What do you most like to do in your free time?

Still, they do set the tone for the interview, and the interviewer’s impression of you. Nobody likes a bad impression, eh? So, just do your best, even if fit questions aren’t the most important.


Notes on written case interview

To pass all the L.E.K. case interview rounds, you also need to prepare specifically for L.E.K.’s written case interview. Here are some tips:

Enhance fast reading skills

Improving your reading speed will help you process data faster, allowing you to single out the important pieces. You can learn the tips to improve your reading speed in this speed reading techniques article.

Craft your data-analysis skills

The ability to analyze data is the core of the hypothesis-driven approach in consulting. You analyze the information to determine the root cause, formulate a hypothesis, and support your suggestion. To enhance your data analyzing skills for your written case interview, practice data interpretation skills (reading charts, tables, graphs…). 

You can also find out more on this with our Numerical Reasoning Package.

Learn to make consulting slides

In the written case interview, your job is to organize the layout of graphs, tables, findings, and recommendations in a “consulting” style (on paper or in PowerPoint). In real consulting work, the PowerPoint engineers (yes I call them that because they’re so good) will add the bells and whistles to create the final slides for your pitch.

We have a whole article on how to craft and present MBB/consulting slides. Check it out to learn the step-by-step guide.

Deliver a timed and solution-driven pitch

The first thing you should do is to allow a specific time limit for each step of the pitch. When that time limit reaches, stop what you're doing (like skimming data) and move on to the next (like structuring the problem). Also, you should spare some time for contingency for any errors occurring.

Second, your presentations and pitches should begin with the conclusions and chart titles with the most important insights. Clients won’t care about the procedures; they want results. So, present the solution, back up with the evidence from your analysis, and recap the pitch.

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