The nature of security in the contemporary world is changing rapidly. Superpower detente, the progress and further prospects of arms control, the collapse of East European communist regimes, and German unification, to name but the most spectacular features, present unprecedented challenges not only for political decision-makers, but also for the mass publics in democratic societies. What are the trends of public opinion on these issues and how do they reflect these changes? By what factors are pertinent public attitudes shaped and what structures do emerge? How can they be reliably assessed and meaningfully analyzed? Which demands flow from the dynamics of public opinion that have to be taken into account in security policy making? These are the key questions addressed by the twelve contributions to this volume. Combining longitudinal and comparative approaches they cover the public dimension of the national security debate in seven Western nations: Canada, Germany, Great Britain, Israel, Japan, the Netherlands, and the United States.