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by RocketBlocks | October 17, 2017


Tennis ball spinning with water droplets in symmetrical pattern

What does Serena Williams' serve have to do with the toughest job interview style out there? A lot. In today's post on mastering the case interview, we're going to unpack what the case interview really is, the core skills it tests and why the best way to prepare is shockingly similar to how Serena practices every day.


The case interview success story

If you rewind fifty years from today, the case interview would barely register on the radar of job interviews. But a lot has changed. Fifty years ago, The Boston Consulting Group was four years old, Bain & Company didn't even exist and McKinsey & Co. was a barely recognizable fragment of the global behemoth it is today. Combined, those three firms rake in around $17 billion in annual revenue and they owe much of their continued success to world class talent. After all, these firms don't own any tangible assets or products. 

So how have these firms secured world class talent decade after decade? The case interview. In fact, the format has been so successful for these dominant consulting firms that the giants of other industries have taken note. Both Amazon and Google have adopted the case interview format in various incarnations for many of their business roles and other tech firms, like Facebook, aren't far behind either.


The preparation game has changed

As case interviews have grown in popularity, the stakes on the preparation side have been upped as well. It used to be that candidates could simply read a few basic case interview books, memorize some popular business frameworks like Porter's 5 forces and combine that with some natural talent and have a decent chance in the case interview. 

Today, that passive preparation won't fly. What's passive preparation? It's a process characterized by a "lean back" experience like reading a book or watching a video tutorial—it can help set context but it isn't a standalone strategy. Serena Williams didn't learn her Wimbledon dominating serve by reading a book and, likewise, the best case interview candidates aren't honing their skills by simply reading either. In fact, the best candidates are actively preparing by devoting significant time to building the skills which will be tested directly in the interviews.

Which skills? Glad you asked—let's jump into those next.


The core case interview skills

You could get a case about a medical device firm looking to enter the Chinese market for the first time or a children's entertainment company that needs a new pricing strategy for digital content. The subject of case interviews will vary widely. However, the skills tested are consistent across cases. Here are the four foundational case skills and why they matter.


Problem structuring: It's tough to overstate how critical this skill is. Consultants have turned problem structuring into an art (see the MECE principle) and they'll expect candidates to demonstrate strong skills here. Why? Well, it matters at every single level of the job, from a Partner breaking up an entire case into large work streams to junior Associates structuring their approach to sizing markets, etc.


Mental math: People always want to ask, why does mental math matter in the world of Excel and iPhone calculators. Quite simply, strong mental math abilities are sought after because it lets consultants quickly prove or disprove hypotheses with quick "back of the envelope" calculations. When you're evaluating thousands of different potential strategies, quickly ruling out ones via simple mental math enables consultants to work effectively.


Charts and data analysis: If there is a "lingua franca" of consulting, this is it. Consultants cull through reams of data in their jobs and when they've got the answer, charts are the vehicle to nicely sum up their findings and highlight the key trends. Aspiring consultants will quickly find that the art of representing an insight via the right chart is a subject approaching near religious debate at any firm.


Communication: Consultants don't just need the analytical chops to get the right answer, they also need the ability to communicate it clearly and create alignment with clients. If you consider consulting from the highest level, the job essentially has two parts: 1) Finding the right answer and 2) Selling the right answer to the client. It is the second part where effective communication becomes a "deal breaker" skill.


Building skills like a boss

The list of skills above might be daunting, but if you take a page out of Serena's book and practice the core skills daily, you'll see a marked improvement. Williams' dedicated practice regimen has gained fame in tennis circles. Despite being the dominant female player in the league today, she's on the court four hours a day practicing serves, backhands, volleys, et al.

The best candidates take the same approach for case interviews. While figuring out what skills to practice isn't tough (just see the list above), but putting in the work is. For a deep dive on preparing for case interviews, check out the Mastering the Case Interview webinar. In it, we cover the anatomy of a case in detail, walk through the examples of how each core skill in tested in a sample case interview environment and recommend a skill building loop that will have you prepping for case interviews with the best of them.

Kenton Kivestu is the Founder and CEO of RocketBlocks, an online platform that helps students prepare for case interviews. Prior to RocketBlocks, he worked as a strategy consultant in BCG's San Francisco Office, launched online ad platforms at Google and led the Zynga mobile poker franchise. He has successfully navigated hundreds of case interviews himself and believes that the case interview is an important recruiting tool that helps simulate the on the job experience. He started RocketBlocks to help candidates hone their analytical skills so they can put their best foot forward on interview day. Kenton graduated as an Echols Scholar with distinction from the University of Virginia and holds an MBA from the Tuck School of Business at Dartmouth.