Institutions generate cooperative benefits that explain why they exist and persist. Therefore, their etiological function is to promote cooperation. The function of a particular institution, such as money or traffic regulations, is to solve one or more cooperation problems. We go on to argue that the teleological function of institutions is to secure values by means of norms. Values can also be used to redesign an institution and to promote social change. We argue, however, that an adequate theory of institutions should not be ‘moralized’ in that they should not be defined in terms of the values they are supposed to promote.