While the rules governing the formation of groups engaging in collective action may have significant impact on group size and behavior of members, most experiments on public goods have been conducted with the subjects in fixed groups or of fixed sizes. We study endogenous formation of groups in...

We report experimental findings on the impact of network structure on decentralized monitoring and punishment in public goods games. In the environments we study, individuals can only directly monitor and punish their immediate neighbors in an exogenously determined network. We examine...