Institutional economics and the concept of equilibrium

Institutionalism did exert a great influence both in the academia and in politics in the interwar period. However, after World War II, it lost ground and was pushed behind the scenes, although some distinguished exponents reached a remarkable success. In the 1970s, a new and very different kind of institutionalism developed. The paper inquires, through the use of the concept of equilibrium, into the evolution of institutionalism, from the classic, through the modern, to the new institutionalism.