Title of an influential 1968 essay by biologist Garrett Hardin, which argued that overuse of common resources is a leading cause of environmental degradation. This was interpreted by some, especially economists and free-market libertarians, to mean that private ownership is preferable to the commons for the stewardship of land, water, minerals, etc. Yet in recent years many have challenged this view on both empirical and philosophical grounds. Professor Elinor Ostrom of Indiana University has been a leading figure in demonstrating the practical utility and sustainability of commons governance regimes, particularly in developing countries. This suggests that the vision of human behaviour implicit in the tragedy of the commons metaphor is not as immutable as many economists assert, and that collective management is an eminently practical governance strategy in many circumstances. The tragedy of the anti-commons is now frequently invoked to describe the problems associated with excessive privatization and fragmentation of property rights, such that collective action for the common good is thwarted. See also Commons” and Common pool resources”.