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 Certified AI Practitioner: Workplace Foundations.
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 module of every program is free with a free account.
- Context Engineering: Decomposing Complex Problems for AI · Critical Thinking and Context Engineering, Certified AI Practitioner: Workplace Foundations
- Breaking an impossible problem into small solvable ones · Engineering Thinking and Elegant Minimalism, Engineering Judgment and Professional Formation
Terms it appears with
Not an alphabetical neighbourhood: these are the terms taught in the same lessons, ranked by how often they appear together.