Domestic Support Operations (DSO) have never been considered a primary mission for the United States military; however, recent experiences of the past decade indicate that the military role is not only a likely one, but also an expanding one. The purpose of this study is to examine the elements of unity of effort in DSO, how they apply in an interagency environment, and what needs to be done in order to respond to potential civil emergencies of the future. The study includes a review of policy and doctrine and examines several case studies: the Federal response to the L.A. Riots of 1992; a brief excursion to the Hurricane Andrew relief effort also in 1992; and military support to the 1996 Atlanta Olympics. The case studies are examined using the author's delineated components of unity of effort as focal points (criteria) for analysis: coordination, cooperation, consensus, and common focus. The study concludes that much progress has been made in enhancing interagency unity of effort since the civil emergencies of 1992. However, new asymmetric transnational threats in the form of Weapons of Mass Destruction (WMD), loom on the horizon. Planning for the 1996 Olympics laid the groundwork to address both crisis and consequence management as components of the Federal response to the detonation of a Weapon of Mass Destruction. Much work still remains in order to develop and integrate local, State, and Federal capabilities and ensure a unity of effort that the American people expect of their government and military.