Two-by-two grids are almost ubiquitous in management circles. They go by many names: BC grids after Boston Consultancy Group, decision matrices, and so on. They crop up in Covey's 7 Habits.

They're extremely useful for concisely articulating a tightly-defined situation and mapping items in order to make decisions. Their weakness is that they may oversimplify and lack nuance.

I used to use important/urgent decision grids quite frequently at work.

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