From the very beginning the Treaty of Rome included basic rules on competition law. However, these rules only covered restraints of competition (‘antitrust law’), not unfair competition law. Since then, the situation has considerably changed. The fundamental freedoms of the treaty as well as secondary community legislation have heavily influenced both fields of law. Even if this development led to an important harmonization of competition law in the Member States, one aspect has stayed rather untouched: the legal consequences of a competition law violation have been left to a large extent to the disposal of the national legislature. As far as the legal consequences in private law are concerned every national legal order has tried to integrate competition law violations into its national tort law (or in some respects contract law) system. In this process, private remedies for violations of unfair competition law have gained a greater practical importance in Europe than those for violations of antitrust law. But even in the latter branch of law, public enforcement is increasingly complemented by private law mechanisms.

The wide variety of solutions which are proposed by national law were the reason for the editors to start the comparative venture within the Trento project on the Common Core of European Private Law. Based on the Common Core methodology (elaborated by Ugo Mattei and Mauro Bussani in the tradition of Rudolf B. Schlesinger and Rodolfo Sacco), i.e. on a questionnaire containing several cases which are discussed and answered by national reporters pursuant to their respective national legal systems and taking into account all legal and extra-legal formants, we have compared the state of the law in fifteen EU Member States.