The goals of health and human security are fundamentally valued in all societies, yet the breadth of their interconnections are not properly understood. This volume explores the evolving relationship between health and security in today's interdependent world, and offers policy guidelines for global health action. This volume underscores three basic principles. First, recent developments in the changing security landscape present enormous challenges for human security and global health. Second, although the connections between health and security are long-standing, the current context of new conflicts, pervasive poverty, and accelerating global flows has brought the fields closer together. Finally, a human security approach dependent upon individual and collective action can identify new strategies for meeting the goals of global health and security. The distinguished contributions to this volume were commissioned by Harvard University's Global Equity Initiative, a research unit supporting the work of,the International Commission on Human Security.