Nemawashi (根回し): going around the roots. In gardening, cutting the spreading roots of a tree one or two years before it is moved, so that fine new roots grow. At work, preparing a negotiation or meeting in advance so that it goes smoothly.
Sannin yoreba Monju no chie (三人寄れば文殊の知恵): when three people gather, they have the wisdom of Monju. Ordinary people who consult together in a group of three produce excellent ideas. Monju is the bodhisattva of wisdom.
Rentai sekinin (連帯責任): joint responsibility. A whole group answers for what one of its members did.