The allocation and exchange of discrete resources, such as transplant organs, pub- lic housing, dormitory rooms, and many other resources for which agents have single-unit demand, is often conducted via direct mechanisms without monetary transfers. Incentive compatibility and ef?ciency are...

An advantage of collective wage agreement is that search and business-stealing externalities can be internalized. A disadvantage is that it takes more time before an optimal allocation is reached because more productive firms (for a particular worker type) can no longer signal this by posting...