The optimal duration of a supply contract balances the costs of re-selecting a supplier against the costs of being matched to an inefficient supplier when the contract lasts too long. I develop a structural model of contract duration that captures this tradeoff and provide an empirical strategy...

In a two-tier industry with bottleneck upstream and two downstream firms producing vertically differentiated goods, we identify conditions under which the upstream supplier chooses exclusive or non-exclusive negotiations, or an English auction to sell its essential input. Auctioning off a...