A3 report
An A3 report is a single-page document, developed at Toyota, that summarises an entire problem-solving effort – the issue, its root cause, the fix, and the result – so it fits on one sheet of A3 paper.
The one-page limit is the point, not a formatting quirk. It forces the kind of careful framing and root-cause analysis that a ten-page report lets you skip past – you can’t hide a vague problem statement behind volume when there’s no room for it. Most A3s follow a Plan-Do-Check-Act structure: define and break down the problem, find the point of cause, take corrective action, then confirm the fix actually worked before sharing it.
Beyond problem-solving, teams also use the same one-page format for status reports and planning exercises like value stream mapping – anywhere a shared, at-a-glance view beats a long document nobody reads in full.
See the 8-step format and a worked example of an A3 report.