We provide an ascending auction that yields an efficient outcome when there are many identical units for sale and bidders have interdependent values and downward-sloping demand. Our ascending auction both extends and generalizes Ausubel's (2004) and yields the same outcome as Perry and Reny's (2002) generalization of Vickrey's (1961) sealed-bid auction. There are two key features of our auction. Bidders are permitted both to express different demands against different bidders, as well as to increase their demands. The equilibrium strategies are closely related to the familiar “drop out when price equals value” strategy of the English auction.

This paper concerns the pattern of contributions to a joint project when commitments and enforceable contracts are not available. We analyse a game in which partners alternate in making contributions to the project until the project is completed. Contributions are sunk when they are made. The game has a unique subgame perfect equilibrium path, which is inefficient in the sense that socially desirable projects may not be completed. By contrast, in a “subscription game” in which the cost of the contribution is borne only if and when the contributions committed to the project cover its cost, the outcome is efficient.

This paper analyses a bargaining model with incomplete information in which the time between offers is an endogenous strategic variable. We find equilibria involving a delay to agreement that is due to the use of strategic time delay by bargainers to signal their relative strength. Under some specifications of the parameters, delay is present in the unique sequential equilibrium whose beliefs satisfy one intuitive restriction. This delay does not vanish as the minimal time between offers becomes small.