Abstract: The lynchpin perhaps even the very foundation of free market environmentalism is the tragedy of the commons. If we do not have private property rights in land, endangered animal species, fish, trees, etc., then there will be a real danger, as the left wing environmentalists charge, of extinction of these resources. Prof. Eleanor Ostrom attempts to show that this is not so; that private property rights are not at all needed if we are to escape environmental degradation of this sort. The present essay is not so much book review as it is an attempt to refute Ostrom, and thereby defend private property rights. In her view, communal rights will suffice; private property is not needed. My claim is that she is incapable of properly distinguishing between stockholders, or partnerships, or groups of people who together own private property, on the one hand, from, on the other hand, communal ownership.