Case study interviews are an integral part of virtually all recruitment processes, for both management consultancies and corporates alike.
Broadly speaking there are two types of Case study interview:
1. The market sizing question (the one with no absolute right answer):
For example, the question may be: how many golf balls are lost on golf courses in Australia each year? Be aware that these can often be thrown at you at an interview to see how you think on your feet. In this situation, you need to be able to present an answer that is plausible and logical and be able to show how you reached this conclusion.
2. Traditional business case:
This is typically a real business problem; one you would be expected to solve as a Case Manager in a consulting firm. What is being tested is your ability to listen and approach a problem in an analytical and structured manner (often using a framework to structure your response, such as the 4C’s or Porters five forces).
A case study is an opportunity for the interviewer to see first-hand how you perform under pressure and how you approach and solve complex problems. Key to this is being able to structure ‘MECE’ (mutually exclusive, collectively exhaustive) possible options or drivers. Practising decomposing business problems into those MECE drivers is probably one of the most important parts of what consulting firms call structuring.
A case study is not only trying to test your quantitative skills and commercial acumen, it is also testing your ‘grit’ – so make sure you don’t give up when faced with a potentially unsolvable problem (keep offering alternative innovative solutions!) and don’t get frazzled in the process. Practice – and lots of it - is the key to being successful in this high pressure situation. Make sure you do a minimum of 2 mock interviews with a current or former consultant (someone experienced in case interviewing) and brush up on basic concepts like break-even analyses, fixed and variable costs, etc., as these tend to come up a lot too.
For further information, below is a starting list of resources and also check consulting firms’ own interview preparation guides too: