There is a body of literature on the subject how self governing groups escape the tragedy of the commons. For example: http://www.amazon.com/Governing-Commons-E

There is a body of literature on the subject how self governing groups escape the tragedy of the commons. For example: http://www.amazon.com/Governing-Commons-Evolution-Institutions-Collective/dp/0521405998 http://www.amazon.com/Governing-Commons-Evolution-Institutio... This is all empirical studies.