The European Court of Justice has profoundly influenced the development of the legal order of the European Union through the elaboration of unwritten general principles of law derived from the fundamental values underlying the national legal systems. This fully revised and updated second edition provides a detailed and systematic analysis of the general principles as applied by the European Court of Justice and the Court of First Instance. It assesses the impact of the EU Constitution on the relationship between the EU and the Member States and the protection of Community rights in national courts.