The link between EU criminal law and the EU regulation of competition is a potentially significant but still largely unexplored matter, in both theoretical and practical terms. In formal terms, there is no cross-reference between the two, and no obvious linkage. But closer acquaintance with the subject raises the question of how, first, the burgeoning development of national criminal law for purposes of enforcing some areas of competition law and policy and, secondly, the highly significant and original EU own-enforcement of its competition rules, which has developed some clearly repressive and penal features without a formal label of criminal law, fit with emergent EU criminal law. The discussion here first of all explores the relevance and use of the methods and concepts of criminal law in competition governance, especially in the European context, and then returns to this matter of the present and possible future relationship between EU criminal law and the competition regime.