Wal-Mart is so large, its reach so great, that it has created an ecosystem in which its suppliers and competitors, and their suppliers and competitors, and their customers, all operate. Wal-Mart sets the metabolism, it sets the rules, of that ecosystem. Wal-Mart has inexorably changed our expectations as shoppers—and the Wal-Mart effect also extends to consumers who never shop at Wal-Mart. Likewise, Wal-Mart has reshaped the companies that supply it—and it has also reset the pace and the competitive landscape even for companies that try to do business outside the Wal-Mart ecosystem.