Do's and Don'ts for Being Hypothesis-Driven at McKinsey

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When problem solving at McKinsey, it's considered best practice to use hypotheses to guide your thinking and work.  Your McKinsey boss will often ask you to be more "hypothesis-driven".  If you are interviewing for a job at McKinsey, your interviewer will expect you to be hypothesis-driven when solving the case interview.  In this post, I'll explain what that means and also provide some tips on what to do and not do when being a hypothesis-driven consultant...

What a hypothesis is and is not...

The hypothesis is your best, educated guess of what the answer is to a given problem.  It is not a shot in the dark - instead, it should be informed by background information, preliminary data analyses, and input from Firm experts.

It should not be based on conjecture or solely on opinion.  Early in an engagement there might not be many concrete facts upon which to base the hypothesis.  But the further you get into a client engagement, the more fact base there should be supporting your hypothesis.


The hypothesis should be considered a living document that is constantly revised and continuously improved as it is tested and new information and/or insights come to light.  It is not permanent and it is not the final answer.   It is definitely not thinking that you know the answer at the beginning of a client engagement - that attitude is what gives consultants a bad name and creates perceptions that they are arrogant know-it-alls. 

What does it mean to be hypothesis-driven?

A hypothesis-driven consultant develops a hypothesis of the answer to a problem early, then focuses on testing and revising that hypothesis over the course of the engagement.  This is also known as "having a perspective on the answer" and considered to be superior to the alternative of searching for an answer in a vacuum.  The hypothesis is used to inform what data needs to be collected, analyses will be performed, and insights must be gained in order to arrive at a final answer.

Important things to do when being hypothesis-driven...

DO:

• Be sensitive to the fact that most non-consultants are not comfortable working this way
• Inform your hypothesis with all available information including situational context
• Involve others - especially your team - in developing and revising your hypothesis
• Test and improve your hypothesis constantly as new information becomes available

Important things to NOT DO when being hypothesis-driven...

DON'T:

• Wait until you have every fact you are seeking - you might be waiting forever
• Waste time trying to make your hypothesis and supporting analyses perfect
• Forget that your hypothesis should be a living document that is continuously improved...
• Fail to question your hypothesis
• Defend your hypothesis blindly
• Adjust data to fit your hypothesis