While the skillsets firms want to see demonstrated in case interviews is fairly static, the medium through which they test them can vary. Here we'll do a quick run through on the different types of case interviews you'll encounter and what special things you should consider in each case. Below, we've listed the Big 4 case types in descending order by popularity and frequency of use.
There are lots of different configurations and case styles. But, put all that aside. The key thing you've always got to remember: all of them are simply a conversation about a challenging business problem. That should be the guiding light." - Jacob Best, former Bain Consultant
This is the most common type of case interview and it's used extensively by BCG, Bain, Deloitte, Accenture and many other firms. The only notable exception in this is McKinsey, who uses more interviewer-led cases. Interviewee-led simply means that the pace, flow and content of the case interview itself will be led by the candidate. The interviewer will of course provide the initial case prompt, but beyond that, the candidate is expected to drive the rest of the case to conclusion. Some interviews may intervene more or less, or be more forth coming with tips and hints, but the expectation is that the candidate will drive the process.
One key thing to realize then is that this interview type will be more effective at assessing one's ability to navigate and lead him/herself through the problem itself (as we discussed above as one type of test on leadership skills).
This is the style of interview used almost exclusively in McKinsey interviews, although we've had numerous reports of Partners straying from the format in final round interviews and doing something which is much more interviewee led. The key difference between this type and interviewee led is that the interviewer will lead the candidate through a predetermined path and thus it will be less of a candidate "choose your own adventure" experience.
The benefit of this type from the firm perspective is a standardized interview, with the hope that that also produces more standardized ratings of candidates. The downside here is that there is less room for the candidate to demonstrate their own skill in structuring, navigating and leading the problem solving exercise. While interviewers will still have candidates do things like create an initial problem structure, regardless of what the candidate proposed, they'll then dictate which bucket of analysis or investigation to do next.
A newer form of case interview that Bain and a handful of other firms have been pioneering is a heavy mix of data analysis plus a presentation. This format is still evolving quickly right now but in most cases candidates are handed a data trove consisting of a mix of slides, datasets and research and asked to cull through it, assemble a recommendation and make a presentation to a group of consultants. Typically, candidates are given 2 hours to review the data set and build a presentation. Then they'll present their recommendation to a group of senior consultants for roughly twenty minutes and then host Q&A.
"In the written cases, you're usually given a deck of slides and some time to review. It's sort of different but you want to follow the same process: structure the problem, find supporting data and propose a series of solutions." - Abhi Tiwari, former BCG Consultant
Format wise, this type of case interview is designed to get even closer to modeling the on the job experience: analyze data, pull together a recommendation and present to the client. Bain in particular has been pushing this because they found that their interview process was starting to overweight the importance of certain soft skills and cultural elements and in turn, down playing the analytical elements. Overall, while this type of case will evaluate all the same soft skills and analytical skills, it gives candidates a little more time to dig into the data, ruminate on it before having present back an answer and recommendation.
This style of case interview is the most unique of all the types and also the rarest. The first major strategy firm to employ group case interviews was the Monitor Group, which was acquired by Deloitte in 2013. Unsurprisingly, the skillset that this interview will tease out more than any others is the candidate's collaborative skills. Firms that utilize a group case are usually particularly interested to see how candidates will interact with each other.
Some of the key collaborative dynamics they'll be looking at are: who is helping drive the discussion forward? Who is ensuring that the different viewpoints are being heard, acknowledge and discussed? How are resolutions between differing points of view being resolved or not resolved and why? To look at one specific example, consider the case of one candidate advocating a factually incorrect position. Does another candidate successfully convince him/her otherwise? Consultants often have to "walk clients" back from incorrect positions and just telling a client "you're wrong" won't cut it, because it will damage the relationship with a client.
"I found the fixed-style McKinsey interviews more interrogative than others. Some of the cases from boutique firms felt more personal, and the interviews themselves felt a little more unpredictable than some of the larger firms. There are differences, but on the whole, it's still a case!" - Richard Smith, former Bain Consultant
Ok, but how many do I have to do?
Good question! The process varies from firm to firm, as you'd imagine, but there is a fairly typical end to end recruiting process that takes place for most firms. Let's take a look at that now.