Examining general principles of law provides one of the most instructive examples of the intersection between EU law and comparative law. This collection draws on the expertise of high-profile and distinguished scholars to provide a critical examination of this interaction. It shows how general principles of EU law need to be responsive to national laws. In addition, it is clear that the laws of the Member States have no choice but to be responsive to the general principles which are developed through EU law. Viewed through the perspective of proportionality, legal certainty, and fundamental rights, the dynamic relationship between the ingenuity of the Court of Justice, the legislative process and the process of Treaty revision is comprehensively illustrated.