PDCA cycle
Definition
PDCA (Plan, Do, Check, Act) is a four-step iterative management cycle for continuous improvement: plan a change, implement it on a small scale, check the results against the plan, and act to standardize or revise based on what you learned.
W. Edwards Deming popularized this cycle in post-war Japan, adapting it from Walter Shewhart's earlier Plan-Do-Study-Act (PDSA) cycle. Deming's work with Japanese manufacturers in the 1950s was so influential that the Japanese Union of Scientists and Engineers named a prestigious quality award after him — the Deming Prize.
The four phases:
- Plan: Identify a problem or opportunity. Analyze the current state. Set a measurable goal. Design a test or change hypothesis.
- Do: Implement the plan on a small, controlled scale. Collect data.
- Check: Analyze the data. Did the change produce the expected result? What did you learn?
- Act: If the change worked, standardize it and scale it. If it didn't, use what you learned to plan the next cycle.
PDCA is the underlying structure of most improvement frameworks. Kaizen events run PDCA over a week. Six Sigma's DMAIC is an expanded version. Agile sprints are PDCA at a two-week cadence: plan the sprint, do the work, check in the retrospective, act by adjusting the next sprint.
Teams draw PDCA loops on whiteboards to frame improvement discussions, plan experiments, and track iterative changes. The circular diagram — four quadrants labeled P, D, C, A — is one of the most common whiteboard drawings in operations and quality management.
Examples
- Support quality: Plan = reduce first-response time, Do = test a new triage script with one team, Check = measure response time for two weeks, Act = roll out script to all agents
- Feature experiment: Plan = hypothesis that a new onboarding step increases activation, Do = A/B test with 10% of users, Check = measure 7-day retention, Act = ship or revert
- Manufacturing defect: Plan = identify root cause of surface defects, Do = adjust coating temperature for one production run, Check = measure defect rate, Act = update standard operating procedure
- Sales process: Plan = add qualification call before demo, Do = pilot with two reps for a month, Check = compare close rates, Act = update sales playbook
Related terms
Snap a pdca cycle. Ship its actions.
BoardSnap turns any whiteboard — including this one — into a summary and action plan.