The growth potential of countries increasingly depends on the effectiveness of their innovation systems in creating, diffusing and using knowledge. A large share of market-based or informal knowledge flows occur within industrial clusters that can be seen as reduced-form innovation systems. Policies to stimulate innovation at national and local levels must both build on and contribute to the dynamics of innovative clusters. This book presents a series of papers written by policy makers and academic experts in the field, that demonstrate why and how this can be done in different national contexts.