This article examines the incentives of contractual parties to design agreements that are left intentionally incomplete with regard to future duties or contingencies. More complete contracts mitigate ex post opportunism and the associated distortions in unobservable investment, but at the cost...

In this article we consider the ways in which the desire for efficient, low-cost adaptation to change influences the tradeoff between the design and duration of long-term contractual relationships. We examine the distortions in contract terms occasioned by nonprice competition for natural gas in...