A summary of the book, The McKinsey Way. Some helpful techniques in here, even if you're not in consulting.

Quoted: One of the most fundamental tenants of McKinsey problem solving is the concept of MECE, mutually exclusive, collectively exhaustive. MECE can be used when developing and listing issues related to the problem at hand. First, the associate must ensure that the list is mutually exclusive, or that every item is separate and distinct. Then, she must check that it is collectively exhaustive, that it includes every issue relevant to the problem. This approach prevents overlap and confusion.