Microeconomic policies ? in particular, industrial and innovation policies ? are appraised and enforced within the framework of the rules relative to free movement and competition. This book introduces the current wave of innovative industrial policies in France. By giving a historical context to their development, the evolution of key economic concepts and theories are put into perspective. In addition, with the aim of articulating horizontal and vertical interventions, this book analyzes the difficulties for public authorities when it comes to linking these ?matrix? policies.