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Node A6 · Acronym decoder

EARS

Easy Approach to Requirements Syntax

What it actually means

A set of five sentence templates for writing requirements — ubiquitous, event-driven (When), state-driven (While), optional (Where), and unwanted-behaviour (If/Then) — that forces each statement to declare its trigger and condition explicitly. Developed at Rolls-Royce for jet engine control requirements, it eliminates most ambiguity defects at the cost of slightly stilted prose.

Where you'll meet it

Requirements style guides; our requirements checker classifies statements against the EARS patterns.

Related terms

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