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Fishbone Diagram -

What is a Fishbone Diagram (aka Cause & Effect Diagram)?

A Fishbone Diagram is a structured brainstorming tool designed to assist improvement teams in coming up with potential root causes for an undesirable effect. Its name derives from its resemblance to the bones of a fish. It is also known as a Cause and Effect Diagram or an Ishikawa Diagram after its creator.

Causes are often grouped into major categories, which are classically defined as the 6 Ms (or the 6 Ps): Man/Mind Power (People), Method (Process), Machines (Program), Materials (Product), Measurements (Policy), and Milieu/Mother Nature (Place).

This tool is used in tandem with The 5 Whys.

5 Whys & Fishbone Diagram Training -

5 Whys & Fishbone Diagram Training
Single Module

For a better understanding of the Fishbone Diagram and an overview of Lean Six Sigma, check out our 5 Whys & Fishbone Diagram Training!

To learn how to use the Fishbone Diagram and how to apply Lean or Six Sigma, check out our free Lean Six Sigma Yellow Belt TrainingGreen Belt Training or Lean Training.

Elisabeth Swan

Elisabeth is a Managing Partner at, the co-author of The Problem-Solver’s Toolkit and co-host of the Just-in-Time Cafe. For over 25 years, she's helped leading organizations like Amazon, Charles Schwab and Starwood Hotels & Resorts build problem-solving muscles with Lean Six Sigma to achieve their goals.