Although the Cold War never went very hot, it still left behind a great deal of fallout. One of the products of the end of the Soviet Union was the re-establishment of the independence of the three Baltic States of Estonia, Latvia, and Lithuania in 1991. Since 1991, those three countries have followed a consistent path of achieving full integration with the West (political, social, economic, and military), and all joined the European Union and the North Atlantic Treaty Organization (NATO) in 2004. Integration with the West and NATO membership, however, also came at the price of considerable and open enmity with the Russian Federation. This book examines the current threat perceptions of the policymakers and policy shapers of the three Baltic States. The three Baltic States have developed a consensus about some aspects of the security threats they face; the most significant is an agreement about the nature and intent of Russian actions carried out against them. Yet, in looking at other aspects of security, we sometimes find significant differences in the national perspectives. Keeping NATO strong and credible requires that the United States, seen by the Baltic nations as the key leader and center of the alliance, have a thorough understanding of the concerns and threat perspectives of its small allies. This monograph recommends several steps that the United States ought to take to help allay the legitimate security concerns of the Baltic allies and to help build a more effective NATO policy to engage Russia over the next decade.