Beng's comments are correct. Having interviewed with Mck in the past, I would add that in your case, you may have to explain why you are 'shifting your focus' (since you have an advanced degree) and why you want to be a consultant. Its useful to show great enthusiasm.On the case question, spend a day looking through Marc Cosentino's book "Case in point" or if it's hard to get, look at the vault guide to case interviews. Since you have little time, I'd concentrate on the methodologies in the 1st chapter of each book and maybe 1-2 examples, no more. McK cases are very quantitative so prepare for a lot of fast mental calculations with plenty of % and 0's. Try to ask many questions, but after a few mins, stop and concentrate on explaining your proposed analysis of the question and your rationale for arriving at an answer. Be very clear about setting out a structure at the beginning (write the steps down) and disciplined about following it through. When working it through, take your time but don't show confusion (even if you feel it) - it is supposed to simulate a client assignement and you don't want your client to lose confidence in you.Spend a few minutes at the end summarising your conclusisons.Since you were invited to McK, you may want to consider also applying to other strat houses (don't have all your eggs in one basket), e.g. BCG, Bain, BAH, etc (those that have offices in Italy). Also consider the quality boutiques like LEK/OCC etc. Good luck.