PDCA Cycle

One of the models that are that lies at the core of management systems is the Plan-Do-Check-Act cycle. Dr Edwards Deming is one of the developers of this model. This simple model is important to management systems and is therefore used as the core model in management system standards.


A documented plan of how you want to run the business using management standards (such as Quality Assurance, Occupational Health and Safety, Environment management) as a framework.

2. DO

Refers to implementing and following the management system. This often requires training and communication.


Refers to the process of checking whether the management system is running as per the management plans. The Internal Audit is a primary checking mechanism for this quadrant. External auditors from certification bodies can also contribute to this section of the PDCA cycle.

4. ACT

When a discrepancy is found between PLAN and DO, the ACT part of the cycle refers to correcting actual and potential problems.

NOTE: The circular arrows on the PDCA Cycle represent ongoing or continual improvement.

If the above sounds difficult to comprehend, it wasn't meant to be. All it is saying is that it is good management practice for an organisation to:

  1. Plan how to meet its objectives (e.g. Mission statement, objectives, procedures, instructions etc.)
  2. Follow its plan (not a bad idea)
  3. Monitor whether the plan is being followed e.g. management, supervisors, inspections, auditing
  4. Take action if either plans are not effective or compliance with the plan is failing.


In many ways, every business does this in one way or another.