Performance Management

Continuous Improvement


Problem Solving Process at Toyota

The 7-step Process, the Four Rules, and the A3 Methodology

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Vadim Kotelnikov


"A problem well stated is a problem half solved."

~ John Dewey



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Toyota A3 Problem Solving Methodology

A3 problem solving methodology helps you to work through business process problems. It is based on Lean / Six Sigma techniques and can be used both in small  and large companies.

①  The basic steps of the A3 method are:

②  Theme or Background (What should be happening?)

③  Current Condition (What is happening? and Context)

④  Cause Analysis (Symptoms and Causes)

⑤  Target Condition (Draw the solution)

Implementation Plan (Actions: Who, What, When, Where)

⑦  Follow Up (How will you know when you have fixed the root cause?)

The 7-step Problem Solving Process at Toyota

Innovative problem solving has helped Toyota become one of the most successful automakers in the world. Toyota can confidently distribute a tremendous amount of responsibility to the people who actually do the work, from the most senior, experienced member of the organization to the most junior. This is accomplished because of the tremendous emphasis on teaching everyone how to be a skillful problem solver.

Problem Solving Strategies: 4 Levels  Download PowerPoint presentation, pdf e-book

The process of becoming a learning organization involves criticizing every aspect of what one does. The general problem solving technique to determine the root cause of a problem includes:

①  Initial problem perception

②  Clarify the problem

③  Locate area/point of cause

④  Investigate root cause (5 whys)

⑤  Countermeasure

⑥ Evaluate

⑦  Standardize

The Four Rules of Problem Solving at Toyota

Harvard professors Steven Spear and Kent Bowen followed some Toyota managers around to see what made the Toyota Production System tick. After studying what was happening on the floor, they coined the term "Community of Scientists." They found that each employee – from the line worker to the design engineer – used the scientific method to solve daily problems.

This scientific method serves as one of the four rules that underlie Toyota's manufacturing process.

The rules are:

Rule 1. All work must be highly specified.

Rule 2. Each customer-supplier relationship is direct. This applies to both  internal and external customers and suppliers.

Rule 3. The pathway for each product and service should be simple, transparent, and direct.

Rule 4. Every employee uses what the company calls the "pragmatic" scientific method to solve problems. The method entails defining specifications, establishing hypotheses, continually testing them and measuring the outcomes.


Using the scientific process as a foundation, Toyota developed what the company calls "A3" thinking and problem solving methodology. It allows problem solvers to get to the key points very quickly. The "do" phase of A3 entails piloting and testing the hypothesis. The "check" phase studies what actually happened. It's an iterative process that never stops.