PDCA (plan–do–check–act) is an iterative four-step management method used in business for the control and continual improvement of processes and products.
A fundamental principle of the scientific method and PDCA is iteration—once a hypothesis is confirmed (or negated), executing the cycle again will extend the knowledge further. Repeating the PDCA cycle can bring its users closer to the goal, usually a perfect operation and output (or “True North”)
PDCA is also known as a system for developing critical thinking. At Toyota this is also known as “Building people before building cars”. Toyota and other lean manufacturing companies propose that an engaged, problem-solving workforce using PDCA in a culture of critical thinking is better able to innovate and stay ahead of the competition through rigorous problem solving and the subsequent innovations (see book The Toyota Way)
Plan: Define the problem to be addressed, collect relevant data, and ascertain the problem’s root cause.
Do: Develop and implement a solution; decide upon a measurement to gauge its effectiveness.
Check: Confirm the results through before-and-after data comparison.
Act: Document the results, inform others about process changes, and make recommendations for the problem to be addressed in the next PDCA cycle.
PDCA steps and checklist
1 Define the Problem
What is the problem (avoid solutions)
VOC and Value clear
Learn from previous improvement actions
2 Collect the facts
On the work floor itself, see what the problem is (gembo)
Measuring the facts
Sketch the process (Value Stream Map)
3 Analyze the facts
Analyze the facts and come to the core (“root cause”), eg by 5xWhy orFishbone diagram
4 Generate solutions
Generate solutions eg via a brainstorming session
Choose the solution
Make a plan and schedule, for example via an A3 form. Request agreement.
Realize and implement
6 Checking and Act
Check whether the problem has been removed and no longer returns. Act in case of inaccuracies
Learn and evaluate