Nailing the written case at BCG and Bain

40+ pages of information to sort through, 1.5-2 hours, 3-5 slides to make... The written case can be a daunting task and time goes by very quickly! Let us give you some tips to nail this, while keeping it simple!

What it is

The written test is basically a mini version of what consultants do.

At BCG, you have 2 hours to sort through a ton of information (usually 40+ pages of graphs, articles) and produce 3-5 slides to answer questions, provided to you in the form an email printout from a virtual partner. Example question include: 'what products should company X focus on?' or 'what market is most attractice to enter and why?'

At Bain, the principle is the same as at BCG you will have less documents, but only 1.5 hours, and the slides will be pre-filled so you don't have to worry to much about the 'story' or flow of the slides. Unlike BCG, calculators are not allowed!

At the end of the prep time, you will have 30-40mn to present your slides and answer questions from the consultant.

Note that only some countries have this written case, so make sure to ask your recruiter what's up.

What to do and not to do during the interview

1. Start with structuring your case

Exactly like a business case, you need to break down the question into a structure that can include levers/issues/hypotheses to understand what data you need to look for. Don't start digging through the data to see what is available! Start with what you would like to know. Standard frameworks can be a good base to start off of.

For example, for a market entry question (i.e., 'should company X enter market Y?'), you would need to understand the market (size, trend, competition, etc), the unit economics and entry costs (revenue and cost per unit, fixed costs and investments), the ability for the client to enter (financials, people, operations) and the entry strategy.

2. Look for the data required in your structure in the documents

Now you understand what you need, you need to find it! Simply browse through the docs. Remember that you might not be able to write on the doc (annoying, I know). Highlight or take note of all the data that matches what you look for, but don't read everything or you will run out of time! If you want to learn to read faster, I recommend the spreeder app!

Also remember that not all the data you look for will be handed to you directly, some might require to be calculated. So be on the lookout for underlying data that might be useful in later calculations! For example, if you are looking for market size, and find data about the market volume, that's useful because, together with unit price, you will be able to get to market size!

Lastly, remember that you are not only looking for numbers but also for qualitative data! For example, in a market entry case, you are also looking to test whether the current company has the skills internally to expand. Maybe you find some bios of current leaders explaning their experience. Then you will need to assess whether they have expansion/market entry experience or not!

3. Transform, interpret the data and make recommendation

Now is the is the time to do some calculations (usually not very complicated) and understand what that means for the questions you are trying to answer. Usually, you will need to compute some numbers (e.g., in the market entry case, yo will need to compte the market size, market share available to company X, maybe broken down into 2-3 segments).

Once you have done this, it's time to make recommendation, usually broken down into the what (should we do it? Is this a good opportunity?) and the how (is strategy A the right one to enter this market or is it B?). Make sure that your recommendations include the answer to all the questions from the virtual partner email

4. Build your slide pack

Once you have a recommendation, make sure that your first slide mentions it in the title. The content of the slide should be an overview of the supporting arguments of this recommendation.

Additional slides should then be a zoom on each argument supporting the recommendation (if possible one slide per argument) with the supporting data. Each argument/slide can be broken down into further 2-5 sub-arguments, in which case, the slide will have 2-5 parts clearly laid out.

5. Present and defend

When you present, make sure to go through the slide title first, which should be your main message and then give an overview of each arguments before going into each sub-arguments.

Be prepared to be challenged by the consultant. Defend your position when reasonable data is available but also listen very carefully for clues on things you might have missed.

How to prepare

Practice makes perfect as usual! At ZeroToMBB, we work on core skills necessary to succeed: framing, math, synthesis and communication and stress management. By doing a lot of business cases, you will improve on these skills, but having an experienced interviewer give you feedback makes you improve 10x faster!

Sign-up for a free preparation package or one of our coaching plan today! 80% of our candidates get an MBB offer and the others their money back when they take 3+ sessions with us.

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