This textbook examines the economic problems of military organizations from an institutional perspective. It discusses the efficiency and effectiveness of military performance, using a capability-based conceptualization. Constitutional, historical and economic considerations complement the analysis. Neither the analysis nor the conclusions depend on any specific armed force, culture, organization, or language. On the contrary, the challenge of defense economics analysis and armed forces management is reduced to a fundamental economic problem, and solutions to this problem are offered. This book is a must-read for students, scholars and practitioners interested in a better understanding of defense economics.