In The post Cold-War era, the United Nations is taking on a larger role in maintaining global order. This effort has manifested itself in the form of Peacekeeping and Peace Support operations, the number, sizes, and cost of which have grown dramatically over the past three years following the breakup of the former Soviet Union. The number of U.N. sponsored peacekeeping operations has tripled since 1990, while the cost has more than doubled. U.S. military forces are involved in some of these on-going U.N. operations, as well as numerous other unilateral Peacetime Contingency Operations (PCOs) of a peacekeeping or humanitarian assistance nature. Concurrent with the growth of U.S. military participation in PKOs and PCOs, is the largest drawdown of U.S. military strength since World War II. The newly published Presidential Decision Directive on peacekeeping (PDD-13) has increased emphasis on U.S. participation in PKOs conducted under UN auspices and clearly puts the Pentagon 'in the peacekeeping business to stay'. Thus, while the Army downsizes, its increasing role in PKOs is likely to continue. Given these unique circumstances of increased emphasis on participation in PKOs and PCOs on the one hand, and decreasing means as a result of the Bottom Up Review (BUR) driven draw down of the U.S. military on the other, what are the implications for U.S. Army war- fighting readiness? To what extent should the roles and missions of the U.S. Army be defined by peacekeeping operations as collective security? These are the issues that will be explored in this paper.