A3 Problem Solving: The One-Page Method

5 min read · Updated July 2026

A3 is a structured problem-solving method that fits on a single sheet of A3 paper. Born at Toyota, it forces clear thinking: understand the problem deeply before proposing a fix, and tell the whole story on one page.

The story an A3 tells

A good A3 reads left to right as a logical story: here is the background and the problem, here is what is happening now, here is the root cause, here is what we will do, and here is how we will know it worked. Because it is one page, it demands you distil the essence.

The sections of an A3

1. Background — why this problem matters.
2. Current condition — what is happening now, with data.
3. Goal / target condition — what "good" looks like.
4. Root cause analysis — why the problem occurs (e.g. 5 Whys).
5. Countermeasures — the proposed changes.
6. Plan — who does what by when.
7. Follow-up — how results will be checked and sustained.

It builds people, not just solutions

The real value of A3 is developing problem solvers. Working through the template with a coach teaches disciplined thinking — understand before acting, use evidence, and involve the people who do the work.