The purpose of this article is to analyze the background leading to the formation of global governance as a research concept and its implication for international security as a policy guide. During the cold war era, international society reflected a pattern of bipolarity in which international order was based on competition and power politics. During the post-cold war era, however, the new concept of security begins to take shape and the rote of the United Nations is increasing, international society therefore has a new expectation toward global governance. Although some scholars are not happy about the Westphalia model, this century-old system continues to operate and the nation-state remains as the basic unit of international relations. Global governance has made international organizations even more important in international security and international conflict will receive better treatment in the future.