Refugee protection depends, minimally, on the identification of agents capable of discharging international obligations in this area of international law. Commonly discussed “agents of justice” include states, IOs, and NGOs. This article focuses on a different set of actors: subnational units (cities, states, and provinces in federal States) and the legal mechanisms they may use to discharge international obligations in the area of refugee protection. I advance three distinct theoretical models for understanding subnational units’ responsibilities vis-à-vis international law: (1) derived (...) delegated responsibilities; (2) derived back-up responsibilities; and (3) assumed responsibilities. I conclude by sketching some ways in which subnational units could play an even more salient role in the promotion of international law. (shrink)