The European Union (EU) is an unprecedented instance of a regulatory state above the nation state. Its underlying idea is to provide joint solutions to shared regulatory problems. For example, the EU issues emission reduction targets for new cars in order to address the problem of man-made environmental pollution. However, and as the above picture illustrates, it is not always an easy task to ensure that the actors responsible for a given problem – for example, car producers – comply with such rules. Member states have a crucial and double role here. On the one hand, they often have to transpose rules from EU Directives into national legislation. Beyond this, however, they also have to put these rules on paper into action, and enforce them to ensure that target groups actually comply. Germany, for instance, has not rigorously enforced EU emission reduction targets vis-à-vis the Volkswagen Company. To put it bluntly, EU law can be perfectly transposed and still fail due to poor implementation performance in practice.