Do political institutions significantly influence policy outcomes? If so, how and why do they make a difference? These essays explain why the differences between governments and national voting systems with a premier and those with a president shape the fundamentals of politics and policy choices in the United States and Japan. The authors explain outcomes ranging from national budgetary priorities through nuclear-power regulations and military-security commitments. They show that the political leadership in both countries is in control of policy, but that political institutions explain why the bureaucracies of the two countries receive different missions and operating procedures. This volume is a powerful contribution to the fields of comparative politics, comparative political economy, comparative foreign policy, and rational choice.