The economic analysis of innovation is important because economic growth in highly industrialized countries and international competitiveness are driven by innovations and technological change. At the same time, marked nation-specific features exist in the structure of innovative activities and in innovative success. For the study of these national characteristics, the concept of national innovation systems constitutes a powerful and widely applied inter-disciplinary framework in modern innovation theory. This book illuminates this concept from different perspectives. Starting from fundamental conceptual and theoretical issues, it describes and discusses the main development lines of the approach of national innovation systems, and goes on to illustrate an empirical application of this branch of research, offering a new alternative for the quantitative comparative study of national innovation systems. This book will be of great interest to economists, scholars and policymakers dealing with innovation, technology, research and development, national innovation systems and international competitiveness.