This volume commemorates the career of Sir Francis Jacobs KCMG QC, who served as British Advocate General at the European Court of Justice in Luxembourg from October 1988 until January 2006. The essays in the volume examine the key developments in EU law over the period that Sir Francis served as Advocate General, one that saw momentous changes in the character of the Union and its legal order. It encompassed the Treaty of Maastricht, which superimposed the Union on the pre-existing European Community, as well as the Treaties of Amsterdam and Nice; the proclamation of the Union's Charter of Fundamental Rights; the drafting of the Treaty establishing a Constitution for Europe; the creation of the Court of First Instance and the EU Civil Service Tribunal; the completion of the single market; and the enlargement of the Union to 15 Member States in 1995 and 25 Member States in 2004. The period also witnessed a profound change in the nature of much academic scholarship on the law of the Union. At the same time, the ECJ continues to grapple with issues which preoccupied it in the 1980s and earlier, such as the relationship between Union law and national law, the circumstances in which individuals should be permitted to seek the annulment of measures adopted by the Union's institutions and the scope of the Treaty rules on freedom of movement. The essays in the volume look at the persistent difficulties that have faced the unique legal system during the period of change. The volume is divided into five sections dealing respectively with: general issues and institutional questions; fundamental rights; substantive law; external relations; and national perspectives. The contributors are distinguished figures drawn from a variety of constituencies, including the national and European judiciaries, legal practice, and the academic world.