Regime complexity and international organizations: UNHCR as a challenged institution

The existing literature on regime complexity has generally focused on its impact on the behavior of states; in contrast, this article explores its implications for international organizations. Many organizations within the UN system were established in the aftermath of World War II, at a time when they held a de facto monopoly in a given policy field. Gradually, however, institutional proliferation has created a range of institutional overlaps that may have complementary or competitive relationships to the referent organization of the original regime. Developing the concept of challenged institutions, this article explores how international organizations are affected by and strategically respond to growing institutional competition. Through a case study of the Office of the UN High Commissioner for Refugees' response to an increasingly competitive institutional environment, it argues that the concept of challenged institutions highlights the dilemmas faced by multilateral organizations in a rapidly changing landscape of global governance.