ABSTRACT
Institutionalism has emerged as one of the major theories aimed at explaining state behaviour and cooperation in world politics.1 The purpose of this chapter will be to present the theory’s basic assumptions, arguments and conditions, as well as some of the more important criticisms that have been levelled against it. At the centre of institutionalist theory lies the argument that institutions may have important effects on state behaviour. In order to understand its develop ment and various aspects, an analysis of the functional approach to interna tional regimes theory is necessary. However, regimes will first be defined.2
