Today, there are over 40 million conflict-induced internally displaced persons (IDPs) globally, almost double the number of refugees. Yet, IDPs are protected only by the soft-law Guiding Principles on Internal Displacement at the global level. Instead of a dedicated international organization, IDPs receive protection and assistance only through the UN’s cluster approach.Orchard argues that while an international IDP protection regime exists, many aspects of it are informal, with IDP issues bound up in a humanitarian regime complex that divides the mandates of key organizations and even the question of IDP status itself. While the Guiding Principles mark an important step forward, implementation of laws and policies based on them at the domestic level remains haphazard. Action at the international level similarly reflects an all-too-often ad hoc approach to IDP issues. Through an in-depth examination of IDP efforts at the international level and across the forty states which have adopted IDP laws and policies, Orchard argues that while progress has been made, new and greater monitoring and accountability mechanisms at both the domestic and international levels are critical. This work will be valuable to scholars, students, and practitioners of forced migration, international relations theory, and the Responsibility to Protect doctrine.