Fish Bone Diagram:

The Fishbone Diagram is a tool for analyzing process dispersion. It is also referred to as the "Ishikawa diagram," because Kaoru Ishikawa developed it, and the "fishbone diagram," because the complete diagram resembles a fish skeleton. The diagram illustrates the main causes and subcauses leading to an effect (symptom).

It is a team brainstorming tool used to identify potential root causes to problems. Because of its function it may be referred to as a causeand-effect diagram.

In a typical Fishbone diagram, the effect is usually a problem needs to be resolved, and is placed at the "fish head". The causes of the effect are then laid out along the "bones", and classified into different types along the branches. Further causes can be laid out alongside further side branches. So the general structure of a fishbone diagram as shown below:


The fishbone diagram is a cause‐and‐effect diagram that can be used to identify the potential (or actual) cause(s) for a performance problem. Fishbone diagrams provide a structure for a group’s discussion around the potential causes of the problem.


The main goal of the Fishbone diagram is to illustrate in a graphical way the relationship between a given outcome and all the factors that influence this outcome. The main objectives of this tool are:

  • Determining the root cause of a problem.
  • Focusing on a specific issue without resorting to complaints and irrelevant discussion.
  • Identifying areas where there is a lack of data.

Feilds Of Application:

The Fishbone diagram could be applied when it is wanted to:

  • Focus attention on one specific issue or problem.
  • Focus the team on the causes not the symptoms.
  • Organize and display graphically the various theories about what the root causes of a problem may be.
  • Show the relationship of various factors influencing a problem.
  • Reveal important relationships among various variables and possible causes
  • Provide additional insight into process behaviors.


  • Helps determine root causes
  • Encourages group participation
  • Uses an orderly, easy-to-read format to diagram cause and effect relationships
  • Indicates possible causes of variation
  • Increases knowledge of the process by helping everyone to learn more about the factors at work and how they relate
  • Identifies areas for collecting data