International regimes may be defined as “sets of implicit or explicit principles, norms, rules and decision–making procedures around which actors’ expectations converge in a given area of international relations.”Principles define the purposes that members are expected to pursue. Rules indicate the specific rights and obligations of member states. Norms establish standards of behavior. The decision-making procedures of regimes provide ways of implementing the principles and altering their rules. Basically, international regimes serve to prescribe and proscribe certain state actions, creating duties and obligations without a hierarchical legal system.
International regimes are often confused with international organizations, such as The World Bank or the UN. While both of these are international regimes they are also bureaucracies with offices around the world. Not all international regimes, however, are bureaucracies like them. For example, the Gold Standard was an international regime without codified rules that emerged based on international behavioral norms.
Robert Keohane argues that international regimes play an important role in explaining the behavior of states in the international system. The underlying principle of the international system is still sovereignty and international regimes should be understood as “arrangements motivated by self-interest.” What this self interest is, however, is not definite, it is elastic and largely subjective. Regimes can affect expectations and in so doing redefine state’s perception of their self-interest.
It is interesting to note that, according to Keohane, states's self-interest, which in fact motivates the creation of International Regimes, is also what makes those Regimes weaker than the states themselves since the sovereignty of the latter still prevails. 
Ultimately, international regimes reflect long-term patterns of cooperation and discord over time. In this way, they help us understand how the relationship among states is more complicated than a more basic distribution of power analysis might reveal, with broadly defined interests that are endogenously determined rather than exogenously defined notions of national interest.
- Keohane, Robert O. After Hegemony: Cooperation and Discord in the World Political Economy. Princeton: Princeton University Press, 1984. Ch 4. Ch 5 Recommended, p. 57
- Ibd, 63.
- Ibd, 57.
- Ibd, 62