Organization without delegation: Informal intergovernmental organizations (IIGOs) and the spectrum of intergovernmental arrangements

The renaissance in the theoretical analysis of intergovernmental organizations (IGOs) has focused on formal IGOs (FIGOs), but many IGOs are subject to no formal treaty and/or have no permanent secretariat. Important examples of informal IGOs (IIGOs) include the G-groups that are the locus of much high-level interaction among states. We develop the spectrum of intergovernmental arrangements to show the wide variation in the formalization of international institutions and theorize when states will choose informal arrangements such as an IIGO over (or in combination with) a FIGO. A paired case comparison illustrates our claims that states use IIGOs when they need flexibility, to protect their sovereignty, to maintain close control of information, to lower short term transaction costs for speed, to minimize bureaucracy and to manage uncertainty during times of crisis. Finally, we examine how institutional choice is influenced by power.