As is stated above, they harmonize their supply chain so that no part of it needs much inventory. For good discussions of this technique, read "Chasing the Rab

As is stated above, they harmonize their supply chain so that no part of it needs much inventory. For good discussions of this technique, read "Chasing the Rabbit" by Steven Spear and "Toyota Production System: Beyond Large-Scale Production" by Taiichi Ohno