It is a great pleasure to introduce and welcome this new book, The Consistent Application of EU Competition Law: Substantive and Procedural Challenges, edited by, and with contributions from, Dr Adriana Alm??an and Dr Peter Whelan. The chapters contained in this book examine the important question of how a number of the procedural and substantive challenges created by Regulation 1/2003 have been dealt with in the 10 years following that Regulation’s coming into force. Prior to Regulation 1/2003, the EU antitrust laws (Articles 101 and 102 TFEU) were enforced principally by the European Commission (the ‘Commission’). In 2004, however, the Regulation transformed the enforcement landscape by abolishing the notification and exemption system and removing the Commission’s exclusive right to decide on the compatibility of an agreement with Article 101(3). These steps have enabled the Commission to focus its resources on, and prioritise, more serious violations of the antitrust laws and paved the way for greater enforcement of the rules at the national level. A more decentralised system has consequently been able to emerge, involving both a network of competition authorities, the European Competition Network (ECN), comprised of the Commission and the national competition authorities (NCAs), and the courts and tribunals of the individual Member States (the national courts). Indeed, both NCAs and national courts are now playing an increasingly important part in the enforcement of Articles 101 and 102.