Toyota has adopted the slogan 'Making only what is needed, when it is needed and in the amount needed!' To achieve this, as soon as an order for a vehicle is received, an instruction is immediately issued to the beginning of the production line to start the production process. The production line is kept stocked with all the necessary parts for assembling any kind of vehicle. Whenever parts are used, the assembly line retrieves an equivalent number of those parts to replace them. A small number of all types of parts are kept in the parts-producing process, and new parts are produced only to replace those parts just used. This JIT production method eliminates wastage and production of unnecessary parts and makes the production process more efficient.