Regime theory

Regime theory is a theory within international relations derived from the liberal tradition that argues that international institutions or regimes affect the behavior of states or other international actors. It assumes that cooperation is possible in the anarchic system of states, as regimes are, by definition, instances of international cooperation.

While realism predicts that conflict should be the norm in international relations, regime theorists say that there is cooperation despite anarchy. Often they cite cooperation in trade, human rights, and collective security, among other issues. These instances of cooperation are regimes. The most commonly cited definition comes from Stephen Krasner, who defines regimes as "institutions possessing norms, decision rules, and procedures which facilitate a convergence of expectations".

Not all approaches to regime theory, however are liberal or neoliberal; some realist scholars like Joseph Grieco developed hybrid theories which take a realism-based approach to this fundamentally liberal theory. (Realists do not say cooperation never happens, just that it's not the norm—a difference of degree).

As stated above, a regime is defined by Stephen D. Krasner as a set of explicit or implicit "principles, norms, rules, and decision making procedures around which actor expectations converge in a given issue-area". This definition is intentionally broad, and covers human interaction ranging from formal organizations (i.e., OPEC) to informal groups (i.e., major banks during the debt crisis). Note that a regime need not be composed of states.

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