Consulting Bible Case Interview Guidelines

Beyond our own interview experiences at McKinsey and Bain, we’ve conducted hundreds of hours of interview preparation (we served 600 clients last year alone!). Trust us, we’ve seen it all – the good, the bad and the very, very ugly. We’ve added this new section in our 3rd edition so you can start off on the right foot with your case practice – using an 80/20 approach to focus on the most important issues and practice to the point where you can nail every case, every time. Even if you don’t work with us, please do yourself a favor – read through this section in its entirety at least once. If you’re one of our premium clients, from here to the end of this book is  a textbook for you – so pay attention!


Core Case Interview Principles


The 16 case studies below aim to test a variety of skills – qualitative and quantitative, ambiguous and precise. To ace them and to ace any case thrown your way, here are the 5 case study principles you must know.


  • Structure is everything, in any and all answers. Use signaling phrases such as “The 3 areas I’d want to investigate” or “The 4 explanations that come to mind,” even if it feels contrived. Why? Because interviewers want to know that you can do it – and being explicit is way to publicly announce you have a skill


  • Unorthodox answers are encouraged – as long as they’re justified with facts, data, and logical reasoning. Why? Because 95 interviewed candidates will regurgitate the same answers when discussing post-merger integration. The 5 candidates who have different, innovative, thorough responses will get offers.


  • Frameworks are helpful, but you can’t rely on them solely. The 2 most important academic ones to us are the 3CP and Porter’s Five Forces. However, they don’t have a financial component – so we’ve put together our own practical frameworks that are more useful for actually solving cases. Just remember – do not rely solely on frameworks! If you do, you will often miss insightful, creative responses that separate you from the pack. Explicitly  build you into answers the opportunity to include creative, innovative solutions.