Case Interview 101. It's really fun to think back over the last 10 years
where we've gone deeper and deeper into insights about firms, about consulting
case interview processes, about the ways that different schools think about and
prepare their students for consulting case interviews - but ultimately, a lot of
this comes back to the basics, and if you don't know the basics, it's really
difficult to know how to get started in your plan for consulting. So, today, we're
laying out seven major areas that you can make sure you check off in terms of
your preparation and your knowledge before jumping into the case interview
process. The case interview process is a huge investment. It takes time, and many
people who are successful also spend money on books and digital resources and
coaching to help them be successful. So you want to make sure that you're ready
to go before we dig in. What firms do case interviews? You are likely to get a
case interview if you are interviewing with almost any consulting firm. That's
where case interviews generally started, and it's where they've stayed, and it's
gotten more pervasive the more consulting firms have added themselves
to the mix. For consulting firms, you can generally expect you're going to do at
least two case interviews in your first round, maybe a mini case interview in
round zero, and then two to three case interviews in your final round.
In addition, internal strategy groups are filled with former consultants, and once
a consultant has gone through an interview process - probably from their
own bias and self selection - they identify that it's a good way to figure
out who is likely to be successful on the job. So, you're likely to find them in
internal strategy groups as well. We are starting to see case interviews pop up
in government hiring, in engineering firms, in product management roles, in
marketing roles, and in many other places across the business world. Those will
generally specify that you'll have a case interview. You won't be blindsided by it
and it won't be a surprise and they also won't downplay it. They'll
explain that it's going to be the hardest part of your interview, but
you're going to find case interviews across all of these different sectors so
be prepared. Point number two - what are case
interviews? Case interviews are different from standard behavioral or fit interviews.
They don't just ask you how you did react in a previous situation. They give
you a hypothetical situation, a hypothetical client, a hypothetical
business problem, even a hypothetical presentation that you have to give, and
they ask you to do what you would do on the job. They're able to watch how you
perform in real time, and this is incredibly insightful because somebody
might say, "I did an amazing job in the past," but you're actually able to see
whether they can do an amazing job when given a new task in the future. Point
number three - how long are case interviews? Case interviews can be as
short as 10 minutes and as long as one hour. The 10 minute interviews skew
towards simple math problems. When I say simple, I don't mean simple to solve but
I mean the problem itself is not complex. It only has one layer or one element to
the questions, such as "what is the market size of (for example) CD covers in the
United States," something that's just a single product, a single market. It's
your job to come up with a number. Those would take about 10 minutes to
solve. The most advanced ones are written case interviews and those will usually
take one hour maybe up to one hour even to prepare, and then a little bit longer -
8 to 10 minutes - to present. So, those interviews are going to be the longest
ones that you'll have the standard interviews are 20 to 30 minutes in the
first round and 30 to 40 minutes in the final round. You'll have a little bit
longer in the final round, which isn't always better; that usually just means
they have more questions, deeper questions, and harder questions to ask
you. Anywhere from 10 minutes to 1 hour is how long your case interview can
last and it will depend on the complexity of the question that you're
being asked, as well as the tasks and the deliverable that you're being asked for.
Number four: what forms do case interviews take?
In our experience, there have been three main forms that most case interviews
take. The first one is verbal, and that's when you're given a pretty open-ended
scenario and you have to work through it verbally. The second one is a written
format, and this will usually be in your final interview and you'll have to go
through a timed process in the office where you'll get all of the information
and you'll have to present it. The third one is a overnight, or a
longer-term written proposal, which is where they'll
ask you to present something - either a piece of work that you've done or
something that's a response to a specific question - but you'll be given
the prompt before you come into the office and you'll be given a certain
amount of time to work on it in advance. All three of these are really
challenging, and you have a slightly different approach for how you handle them.
Our recommendation if you're preparing for multiple ones of those is
that you actually start with the verbal preparation. It's usually the hardest and
the most unfamiliar for most of us based on our work and our educational
background. If you have a handle on that piece, then pulling together the written
and also the written overnight case will be a lot easier for you. Number five: what
can you bring to a case interview? Probably most important is what you
cannot bring. You cannot bring a calculator. Most case interviews are
going to involve math, and without a calculator, how are you going to do it well?
You're going to need the other things that will be handy. First of all, you can bring
your brain - definitely try to do that. Not everybody does into the case interview!
but in terms of actual practical things - you can bring paper. You can bring
something to write on, like a folder, so that you have something if you're not
sitting at a table. You can bring a pen or a pencil, whichever one is more
comfortable for you to use. Usually, you're not going to end up erasing
things. You're going to scratch them out, so pen or pencil are totally fine. And then,
you can bring something to drink, like water. You usually will be offered coffee or
water in the interview you won't have much time to engage with that you won't
have a lot of time to sit back and take sips of water as you go, but it can still
be helpful, both before the interview especially if you're going to do a lot of
verbal work, and also right after that interview. In
addition, we recommend that in a small pocket or in a bag you keep your phone
on airplane mode or totally off inside the interview, and some mints or some gum -
something to refresh your breath in between your interviews. Number six: do you
have to do math? Yes, you have to do math. Yes, you have to do math out loud. Yes, you
actually even have to do math in your head, and this is often one of the
scariest parts of case interviews. The term for the math you have to do in case
interviews is mental math, which doesn't mean that you have to be a human
computer, it just means that you have to simplify math and do it without the aid
of a calculator, and even in Deloitte Consulting interviews for Human Capital,
you're going to have to do math. So, you will have to do math! Be prepared for the
math part, and don't be blindsided by it. Finally, number seven: do I have to
practice? I'm generally a pretty smart person, I interview very well, do I have
to practice for the case interview? This is a common question that we get and our
answer is: "Absolutely, yes!" In fact, from my own experience, I thought
that I didn't need to practice. Well, I thought I needed to practice a little
bit, so I did one mock case interview. That was all I planned to do. In that case
interview, the interviewer told me that I was the worst that she had ever seen,
that there was absolutely no way that I would get a job if I only did that one
interview, and I really needed that kick in the pants. Doing case interviews is
really different than doing other kinds of interviews. They aren't the
backward-looking fit or behavioral interviews, and you
can't rely just on charm and personality. You have to be ready for the specific
tactics, the business problems, and the structure of a case interview. If you're
interested in more information about how to succeed in the case interview, we
would love to help. If you have questions about case interviews, please
reach out to us at www.managementconsulted.com or on social.