In their article in this issue, Singleton and Taylor ask why some groups of users of a commons are able to resolve their collective action problems on their own and others are not. They argue that when groups approximate a community of mutually vulnerable individuals, they are able to develop...

Ignoring the impact of changes in physical capital on a form of social capital - the rules used in farmer-organized irrigation systems - can lead to the unintended consequence that the physical capital is not as productive as intended. Analysis focuses on the choice of rules made by farmers in...