U.S. national security is a subject that has been under intense scrutiny since the end of the Cold War. What constitutes such security for the United States as this country approaches the new century? Are the ends, ways, and means of our national security and national military strategies sufficient to provide for the nation's future? And above all, as this country celebrates the 50th anniversary of the National Security Act of 1947, are the institutions that resulted from that act still sufficient for the post-Cold War era? With these questions in mind, the Strategic Studies Institute and Dickinson College's Clarke Center co-sponsored the series of lectures on American national security after the Cold War which are contained in this volume. The lectures take four different, yet complementary, perspectives. Professor Ronald Steel reminds us of the intellectual revolution embodied in the act that moved America from the concept of "defense" to one of "national security" and relates this concept to our attempts to define post-Cold War national security interests. Dr. Lawrence Korb reviews the evolution in our national security establishment since the 1947 act. Dr. Morton Halperin's focus is the continuing tension between secrecy in the name of national security and the openness required in a democratic society, with a commentary on continuing threats to civil liberties. In the concluding essay, Ambassador Robert Ellsworth surveys the key strategic challenges facing the United States as we enter the 21st century.