The seminar provides an overview of the role of the Court of Justice of the European Union (CJEU) in shaping and enforcing EU criminal law. The seminar will discuss in detail the preliminary reference procedures in which national judges can refer questions of interpretation and validity to the CJEU, where specific reference to criminal law issues will be made. The seminar will also address what the end of the transition period in 2014 will practically mean in the enforcement of EU criminal law, as infringement procedures will also become available in the field of EU criminal law. The seminar will furthermore focus on the CJEU’s role of interpretation in shaping EU criminal law. In this context, both the CJEU’s influence on doctrinal themes of criminal law and specific EU instruments will be examined.