How can we maximize the common good? This is a central organizing question of public policy design, across political parties and ideologies. The answer typically involves the provisioning of public goods such as fresh air, national defense, and knowledge. Public goods are costly to produce but...

We consider truthful implementation of the socially efficient allocation in a dynamic private value environment in which agents receive private information over time. We propose a suitable generalization of the Vickrey-Clarke-Groves mechanism, based on the marginal contribution of each agent. In...