Gift exchange experiments have demonstrated that norms can affect labor market outcomes and provided an explanation for involuntary unemployment. However, conflicting results from laboratory and field experiments have questioned the relevance of gift exchange and helped spark an ongoing debate...

A large and growing literature has demonstrated that explicit incentives, such as enforceable contracts, can lead agents to withhold effort. We investigate when this behavioral result arises. In an extensive laboratory experiment, we find that imposing control through an enforceable contract is...