For experienced hires it's usually more about your expertise and background.
Let's say you have a lot of experience in financial services industry, most likely you will be hired for an experienced role in this industry, will be interviewed by interviewers from that industry, and most likely they will discuss situations/cases from their background which is again financial services. Obviously there are exceptions from this rule, but tactically speaking I would review your area of expertise to be up-to-date with latest trends and developments, and to prepare for cases in that area.
Depending on your level of seniority, the interview process could be completely customized to you. Recently I was coaching 2 partners of a tier-2 consulting firm to switch to associate partner role at McKinsey. The interview process was organized as follows (for each of them individually):
- 4 interviews focusing on motivation for joining McKinsey and in-depth discussion of their expertise/background
- 4 interviews similar to case and personal fit (although obviously on partner-level the requirements and focus is a different one)
- 4 relatively unstructured interviews mainly about personal fit, industry trends and issues as well as potential future engagements as well as their contribution to the firm in terms of revenue and intellectual growth
Depending on your specific situation case interview might not be the most important aspect to consider, so please make sure that you are heading into the right direction with your prep!
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