Radical, revolutionary improvement of a value stream to quickly create more value with less waste; sometimes called kakushin. 

An example of kaikaku is moving equipment during a weekend so that products that were previously manufactured and assembled in batches in isolated process dumps are henceforth made in single-piece flow in a compact cell. Another example is rapidly switching from stationary to moving assembly for a large product such as a commercial passenger jet. Also called breakthrough kaizen, to distinguish it from more gradual, step-by-step kaizen.