Invented by Edwards Deming, the Deming Cycle provides a framework for continuous improvement of business process. It can be summed up in four words:
  • Plan: determine the action you intend to take, as well as the steps required to achieve it. Design the new process (the "to-be" state).
  • Do: Execute the plan. Implement the new process.
  • Check: Measure the outcome of the plan. This required identifying measurable outcomes of the new process.
  • Act: Determine what needs to be done to improve the process.
...which brings us back to Plan. Once gains are made, some standard (such as ISO 9000) is used to consolidate gains and retain the new level of quality.

Leveraging the Deming Cycle requires that some sort of metric be available for assessing the results of each change. Without a way to measure, the process cannot be managed.

Deming designed this around industrial processes, but can be applied elsewhere, such as IT. He put this into practice to rebuild Japan after World War II.
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