Ishikawa diagram

A tool that has proven itself in the automotive world

Everyone knows about the international reputation of the Japanese brand Toyota: many people are still unaware of the origin of its success story. The development of quality tools took place in a difficult context of national recovery in Japan in the 1950s. After the Second World War, quality improvement became a national priority. A prominent professor of the JUSE Japanese Union of Scientist Engineers named Kaoru Ishikawa came up with the concept of the fishbone diagram.

What is an Ishikawa fishbone diagram?

Also known as the cause and effect diagram, this tool allows decision-makers in an organisation to look for the causes of a problem through a graphical representation.

The fishbone diagram is a risk matrix. It classifies the categories of causes inventoried according to the mnemonic method or the categories of why a problem exists. It is a powerful tool for moderating a brainstorming session between quality managers and decision-makers, in order to sort out all the ideas and arrange them for the implementation of a project.

How to integrate the 5M diagram into your organisation?

Thanks to the diagram and the representation of the arrows and sub-arrows, action plans can be drawn up to solve the problem.

During meetings, setting up this diagram meets the objective of accurately visualising the risk matrix identified by the ideas exchanged. The 5M law assumed by the Japanese researcher's diagram aims to structure the search for and analysis of defects by going back to the tree of causes:

  • M1 risk Manpower, e.g. a problem of management, poor training and competence, organisation, lack of motivation or communication…
  • M2 Material or equipment and machinery, for example a problem related to settings and software or simply unsuitable tools
  • M3 Method, i.e. missing or inappropriate instructions
  • M4 Materials, identifying problems with the inputs used (quality of raw material, supply)
  • M5 Environment, problems related to the environment and working conditions.

Calling on a firm to support your quality approach

Extrend Consulting helps you to integrate the principles of the diagram that has proved its worth at Toyota through various actions:

  • training on the tool
  • integration of the tool into your non-conformity management system: analysis of causes, definition of corrective actions