Ishikawa Diagram 5M

1. What’s a Fishbone Diagram?

A fishbone diagram (also called an Ishikawa or cause-and-effect diagram) is used to figure out why a problem is happening. Picture a fish: the head is the problem you’re solving, and the “bones” are potential causes. You organize these causes into categories, like People, Processes, or Technology.

This tool was invented in the ‘60s by Japanese quality control expert Kaoru Ishikawa. It’s still a go-to for businesses using Lean, Six Sigma, and other problem-solving methods.

2. Why Use It?

Fishbone diagrams help you move past the obvious symptoms and find out what’s really going on.

• Structure your thinking: You don’t miss key causes because everything’s laid out in one place.
• Collaborate better: Teams from different departments can share insights.
• Prevent quick fixes: By focusing on root causes, you avoid bandaid solutions that won’t last.

3. How It Fits into Lean Problem Solving

In Lean problem-solving, a fishbone diagram helps teams drill down into causes and prioritize fixes. It pairs well with other methods like A3 problem-solving and the 5 Why’s. Think of it as a starting point to organize your thoughts before deciding on countermeasures.