What is Fishbone? When and How is it Applied?

Sena Düzgün (Writer) 25 April 2024

What is a Fishbone?

Developed in 1943 by Koru Iskikawa, the Fishbone Diagram is also known as the Ishikawa diagram.
The technique helps structure the process of identifying the causes and sub-causes of a problem.

When to Use a Fishbone Diagram?

When identifying the possible causes of a problem, especially when thinking in a team becomes monotonous. 

How to apply the Fishbone Diagram? 

  1. Agree on what the problem is 
  2. Brainstorm about the main causes of the problem. 
  3. Categories of causes are subdivided and written within the framework of the main arrow. 
  4. Brainstorm all possible causes of the problem. "Why did this situation arise?" is asked. Each time an idea or thought comes up and is answered, the facilitator writes it down in the appropriate category. Some reasons can be rewritten if they relate to more than one category.
  5. Then the question "Why did this situation occur?" is asked again separately for each reason. 
  6. In order to branch the reason, sub-causes are written. The question "Why?" is continued and reasons are generated at deeper levels. The layers of branches indicate causal relationships. 

Ideas ignite each other like electric currents.