Fishbone Diagram


A fishbone diagram is a type of root cause analysis. By using a fishbone diagram one is able to identify and organize causes to a problem so that the causes can be prioritized for further investigation.  The diagram is intended to show:

  • The problem (or effect)
  • The categories of the causes of the problem
  • The specific causes of the problem

How To Create a Fishbone Diagram

Once a problem is identified, create the body of a fish on a large piece of paper, butcher block or flip chart. The problem is the “head” of the fish. Label the categories of causes – (Process, People, Machines, Environment), and then brainstorm the specific causes of the problem as a team. Remember, you can be creative and use categories other than those mentioned here (i.e. Software, Market Conditions, etc.).


  • Always identify the causes in a team environment
  • Team members should include process owners, process supervisors, practitioners, and subject matter experts
  • Be flexible with the categories of causes

The purpose of a fishbone diagram is to identify causes to a problem through categorization and determine whether the causes are within or are outside of the control of the team / process owner. Causes within the control of the team / process owner can then be prioritized for future potential investigation / waste elimination.

A fishbone diagram can be used after process mapping the “current state” and used to identify innovation opportunities.

Adjust the cause categories to fit the problem – for example, it may make more sense to use causes such as technology, vendors, and training when brainstorming causes for problems in inventory / receiving for purchasing transactions. It may be effective for the team to brainstorm specific problems first (onto sticky notes), and then determine the categories (cluster and find commonalities).