Toyota's JIT Revolution

Developed by the Japanese, the JIT production system was one of the most significant production management approaches of the post World War II era. The system comprised a set of activities aimed at increasing production volume through the optimum use of inventories of raw materials, work-in-process, and finished goods. In a JIT production system, a workstation gets a part just in time, completes its work and the part is moved through the system quickly.

JIT was based on the principle of producing only what is needed and nothing more than needed. The Japanese believed that anything produced over the quantity required was a waste. Cho defined waste as, "Anything other than the minimum amount of equipment, materials, parts and workers (working time) which are absolutely essential to production." JIT did not allow any surplus as it believed that "effort and material expended for something not needed now cannot be utilized now." (Refer Table I for requirements and assumptions of JIT).