The success of the four core freedoms of the EU has created fertile ground for transnational organised crime. Innovative, transnational legal weapons are therefore required by national authorities. The availability of data on criminal convictions is at the forefront of the debate. But which mechanism for availability can be used effectively while at the same time respecting an increasingly higher level of data protection at national level? In the fluid, post-'Reform Treaty' environment, the EU is moving towards the creation of a European Criminal Record which will ultimately secure availability of criminal data beyond the weaknesses of Mutual Legal Assistance mechanisms. Examining the concept of a European Criminal Record in its legal, political and data protection dimensions, this multidisciplinary study is an indispensable exploration of a major initiative in European Criminal Law which is set to monopolise the debate on EU judicial co-operation and enforcement.