History matters. It matters not only because people can learn from the past, but because the present and the future are connected to the past by the continuity of a society's institutions. Today and tomorrow's choices are shaped by the past. And the past can be made intelligible only as a story of institutional evolution. This story focuses on the problem of human cooperation--specifically, the cooperation that permits economies to capture gains from trade. Economic growth depends upon the evolution of institutions that create a hospitable environment for cooperative solutions to problems associated with trade. Not all human cooperation is socially productive, of course; twentieth-century history provides many examples of cooperative efforts undertaken in the service of ill-advised or destructive goals. In analyzing human cooperation, therefore, people also need to be concerned with the evolution of institutional frameworks that induce economic stagnation and decline. The purpose in each case is to explain the structure and performance of economies over time. In this article, the author argues that the U.S. Constitution is one example of an enduring institutional framework. (Contains 2 notes.)