To be most effective kaizen must operate with three principles in place:
People at all levels of an organization can participate in kaizen, from the CEO down, as well as external stakeholders when applicable. The format for kaizen can be individual, suggestion system, small group, or large group. At Toyota, it is usually a local improvement within a workstation or local area and involves a small group in improving their own work environment and productivity. This group is often guided through the kaizen process by a line supervisor; sometimes this is the line supervisor's key role.
While kaizen (at Toyota) usually delivers small improvements, the culture of continual aligned small improvements and standardization yields large results in the form of compound productivity improvement. Hence the English usage of "kaizen" can be: "continuous improvement" or "continual improvement."
This philosophy differs from the "command-and-control" improvement programs of the mid-twentieth century. Kaizen methodology includes making changes and monitoring results, then adjusting. Large-scale pre-planning and extensive project scheduling are replaced by smaller experiments, which can be rapidly adapted as new improvements are suggested.
In Japanese this is pronounced "kaizen".
In Chinese this is pronounced "gai shan":
In Japan, after World War II, American occupation forces brought in American experts in statistical control methods and who were familiar with the War Department's Training Within Industry (TWI) training programs to restore the nation. TWI programs included Job Instruction (standard work) and Job Methods (process improvement). In conjunction with the Shewhart cycle taught by W. Edwards Deming, and other statistics-based methods taught by Joseph M. Juran, these became the basis of the kaizen revolution in Japan that took place in the 1950s.
The Toyota Production System is known for kaizen, where all line personnel are expected to stop their moving production line in case of any abnormality and, along with their supervisor, suggest an improvement to resolve the abnormality which may initiate a kaizen.
The cycle of kaizen activity can be defined as:
Masaaki Imai made the term famous in his book, Kaizen: The Key to Japan's Competitive Success.
Apart from business applications of the method, both Anthony Robbins and Robert Maurer have popularized the kaizen principles into personal development principles. The basis of Robbins' CANI (Constant and Never-Ending Improvement) method in kaizen is discussed in his Lessons in Mastery series.
In their book The Toyota Way Fieldbook, Brijesh Rawat, Jeffrey Liker, and David Meier discuss the Kaizen Blitz and Kaizen Burst (also called a Kaizen Event) approaches to continuous improvement. A Kaizen Blitz, or rapid improvement, is a focused activity on a particular process or activity. The basic concept is to identify and quickly remove waste. Another approach is that of Kaizen Burst, a specific Kaizen activity on a particular process in the value stream.