This article shows how contracts are the institutional foundation of a market economy. Contracts create wealth, allocate risk and are based on consent. There is no perfect competition and the markets are characterized by a number of failures; therefore, contracts are not perfect. However, the existence of these failures does not undermine the importance of contract and consent. A common critique of the market economy is that most transactions are based on some form of coercion. The authors try to address this misconception by showing that a contract is the result of coercion not in cases where a choice is hard for a party but when it offers a choice the party does not want to have.