States now delegate substantial policy authority to a host of international organizations (IOs). The chapters in this volume describe patterns of delegation by states to the multilateral development banks (MDBs), the International Monetary Fund (IMF), the European Union (EU), United Nations Security Council (UNSC), the World Trade Organization (WTO), World Health Organization (WHO), and the European Court of Human Rights (ECHR), the European Court of Justice (ECJ), and others. Many of these agents have been delegated greater authority by states – or have carved out greater autonomy for themselves – and are deeply integrated into the structure of global governance.

This chapter does not summarize the preceding chapters, but briefly highlights several themes. We conclude that delegation to IOs is remarkably similar in cause, structure, and effects to delegation within states. Principal-agent (PA) theory, which has proven useful in understanding patterns of delegation in the domestic arena, is equally applicable and powerful in explaining delegation to IOs. Most of the chapters in this volume focus on the design and efficacy of institutions to control agent opportunism; this is largely internal to the relationship between principals and agents. Incorporating the role of third parties (TPs), including the many NGOs that now make up global civil society, is the research frontier. We highlight the role of NGOs as potentially important actors in providing information that is essential to the success of international delegation. Thus, this chapter is an unusual conclusion for a collaborative volume.