International actors have been involved in the administration of territories since the 19th century. The early experiments of the League of Nations in territorial administration have broken new boundaries in this regard. The UN practice in the field of peacemaking, and the more recent engagements of the international community in Bosnia-Herzegovina and Iraq, show that international administration is likely to be with us for some more time. Yet, until now, international practice has not yet developed satisfactory methods to adjust the exercise of public authority within the context of international administration to modern standards of international governance and public legitimacy. This article revisits the prevailing conceptions of authority in international territorial administration. It argues that contemporary models of international authority should be re-conceptualized in light of cosmopolitan principles, such as functional limitations to public authority, diversified accountability models and an origin-neutral application of governance standards.