Renegotiation of Sales Contracts

Contracts adopted with later renegotiation in mind may take simple forms. In a principal-agent model, if renegotiation may occur after the agent chooses efforet, the principal protects against unfavorable renegotiation by "selling the project" to the agent via a sales contract. If only singleton (single-scheme) contracts are feasible, the equilibrium initial contract must be a sales contract if the principal's renegotiation position will be inherently inferior in the sense that (a) the agent will have the bargianing power; (b) the principal will not observe the agent's effort, and (c) the agent has the talent, i.e. a rich set of feasible efforts, to exploint contractual nuances. Renegotiation necessarily occurs, and it yields (second-best) efficient allocations. Even when meny (multiple-scheme) contracts are available, if the selection of a scheme from a menu entails any cost, then the final contract is a singleton and equilibrium renegotiation occurs. If there is any complexity cost to specifying a menuy, the initional contract must also be a singleton; it is necessarily a sales contract if the agent has talent. A weak forward induction refinement criterion is used to obtain these results.