kaizen

Kaizen is a Japanese philosophy that translates roughly as "change for the better" or "continuous improvement." In business, it denotes practices aimed at making small, ongoing changes to processes, products, and services to improve efficiency, quality, and customer value. The concept emerged in postwar Japan and gained global influence in the late 20th century, notably through Masaaki Imai's 1986 book Kaizen: The Key to Japan's Competitive Success.

The core idea is that many small improvements, implemented by workers at all levels, yield larger gains over time. It emphasizes eliminating waste (muda), reducing variability, standardizing work, and fostering a culture of experimentation. Improvement is typically achieved through a repeating cycle of planning, doing, checking, and acting (PDCA).

Common tools include gemba walks, the five Whys root-cause analysis, Kanban boards, visual management, and standard work. Kaizen events, or blitzes, are short, structured improvement projects that bring teams together to address a specific process.

Applications: the approach is a central element of lean manufacturing and the Toyota Production System and has been applied in manufacturing, services, healthcare, and public administration. It is usually supported by leadership commitment, training, and a system for suggesting and implementing improvements. Some criticisms note that kaizen programs can become mere efficiency drives if not tied to broader goals, resources, and fair workload.

Variants and related concepts: 'kaikaku' denotes radical, step-change reform; 'kaizen events' are targeted, time-bound improvement activities; 'continuous improvement' is the broader term that encompasses kaizen.