New Institutional Economics is increasingly involved in questioning the basic assumptions of economic theory but rather than being a homogenous field it encompasses a particularly broad domain of theories which vary in approach, research object, and methodology. In particular the concept of rationality is a rich source of dispute. In fact, the history of New Institutional Economics presents a bifurcation between on the one hand approaches which are reminiscent of the old Institutional Economics, and on the other hand, types of NIE theories which opt for analytical strength by limiting the...