This Essay considers the substantive and institutional aspects of an economic theory of contract regulation. It lists the various functions that analysts have assigned to contract regulation and briefly discusses the substantive wisdom and institutional feasibility of performing those functions. The essay tentatively concludes that the state should enforce contracts, supply vocabularies that are useful in writing contracts and supply default modes of economic organization, such as a corporate or bankruptcy code. Other possible state functions, such as supplying efficient default rules for use in contracts, may be beyond the ability of government to perform well.