Plan, Do, Check, Act

An improvement cycle based on the scientific method of proposing a change in a process, implementing the change, measuring the results, and taking appropriate action (see illustration). It also is known as the Deming Cycle or Deming Wheel after W. Edwards Deming, who introduced the concept in Japan in the 1950s.

The PDCA cycle has four stages:

Plan:Determine goals for a process and needed changes to achieve them.
Do:Implement the changes.
Check:Evaluate the results in terms of performance.
Act:Standardize and stabilize the change or begin the cycle again, depending on the results.