States influence competition in the market in various ways. They often act themselves as market participants through state-owned enterprises. They regulate markets and specific sectors of the economy such as public utilities in particular. In some instances, market regulation explicitly aims to promote competition in the market. In other instances, regulatory schemes and decisions may inadvertently distort competition or openly promote conflicting objectives and even anti-competitive goals. Furthermore, states can distort competition among firms when they act as purchasers of goods and services as well as when they grant subsidies to individual firms. This book assembles contributions by competition law scholars who present new insights on the diversity of problems and challenges arising from state-initiated restraints of competition in jurisdictions from all around the world, not only including the EU and the US, but also Latin American countries, China, India and Australia.