MECE (Mutually Exclusive, Collectively Exhaustive)
A structuring principle long associated with McKinsey as an institutional practice and made widely accessible through Barbara Minto's work The Pyramid Principle: a good set of pieces does not overlap (mutually exclusive) and together covers the whole problem with no gaps (collectively exhaustive). The core test for a sound decomposition, used as a diagnostic ideal rather than a rigid law, since some problems are intentionally iterative or overlapping.
Defined in 2 GAGE programs, which carry 2 distinct definitions of it. The wording above is taught in AI Literacy & Professional Conduct.
How each discipline defines it
The same term does different work depending on who is using it. These are the definitions as each program teaches them, unedited.
A structuring principle long associated with McKinsey as an institutional practice and made widely accessible through Barbara Minto's work The Pyramid Principle: a good set of pieces does not overlap (mutually exclusive) and together covers the whole problem with no gaps (collectively exhaustive). The core test for a sound decomposition, used as a diagnostic ideal rather than a rigid law, since some problems are intentionally iterative or overlapping.
A test for a clean decomposition. Mutually exclusive means no two sub-problems overlap in what they solve. Collectively exhaustive means the full set of sub-problems, taken together, actually achieves the original goal, with no gaps. Originally developed as a management consulting method by Barbara Minto at McKinsey and Company in the 1970s.
Where it is taught
The exact lessons this term appears in. The first 7 topics of every program are free with a free account.
- Context Engineering: Decomposing Complex Problems for AI · Critical Thinking and Context Engineering, AI Literacy & Professional Conduct
Terms it appears with
Not an alphabetical neighbourhood: these are the terms taught in the same lessons, ranked by how often they appear together.