PDCAsyklusen

PDCAsyklusen, known internationally as the PDCA cycle, is a four-step management method used for continuous improvement in business and manufacturing processes. The acronym stands for Plan, Do, Check, and Act. The cycle was first described by Walter Shewhart in the 1920s and later popularised by W. Edwards Deming in the 1950s as a key component of the Toyota Production System. Shewhart’s statistical quality control practices provided a quantitative foundation, while Deming extended the concept into organizational learning and systemic quality improvement.

In practice, the Plan phase involves setting objectives and identifying processes necessary to deliver desired results. The Do phase implements the plan on a small scale to test functionality. During Check, data gathered from the implementation are analysed against the objectives, revealing gaps or successes. The Act phase consolidates learning by adapting the processes, standardising successful practices, and planning further refinements. By constantly cycling through these stages, organisations can embed a culture of data‑driven decision making and incremental change.

The PDCA cycle is valued for its simplicity, adaptability across sectors, and emphasis on empirical evidence. It has been adopted in healthcare quality management, software development, and educational assessment, among others. Critics argue that the cycle may oversimplify complex systems or lead to bureaucracy if not applied with genuine commitment. Nonetheless, PDCAsyklusen remains a cornerstone in continuous improvement frameworks worldwide.