There has been a dramatic expansion in the size, scope and capacity of non-state actors around the globe in the last three decades. Providing social services, implementing development programs, participating in international conflicts, non-state actors have played important roles, especially in regions where the government presence is weak. The Middle East is rife with both important humanitarian non-state actors delivering social services as a complement to government action and violent non-state actors operating outside domestic law and international norms. The commonality in both examples is the way in which the non-state actors establish private authorities in the spaces where state sovereignty is weak or absent, and legitimate it in terms of identity, religion, services provided or nothing but violence. This leaves numerous questions to be answered.