Lean Manufacturing was developed in Japan after the Second World War. The basic concept is "continuous improvement". You may often hear the word "Kaizen" associated with lean manufacturing. "Kaizen" is derived from the Japanese words “kai” and "zen". Kai means to fix, correct, improve or change. “Zen” simply means good. So when you put these words together it means "change good" or "correct good". This Japanese system of continuous improvement does not target a small section of the work force or management, it is designed to affect each and every aspect and area of the company. Kaizen must be implemented and practiced from top level management down to the lowest paid employee in order to be successful.