Luxembourg has long been a prominent supporter of European political and economic integration. In efforts foreshadowing European integration, Luxembourg and Belgium in 1921 formed the Belgium-Luxembourg Economic Union (BLEU) to create an inter-exchangeable currency and a common customs regime. Luxembourg is a member of the Benelux Economic Union and was one of the founding members of the European Economic Community (now the European Union). It also participates in the Schengen Group, whose goal is the free movement of citizens among member states. At the same time, Luxembourgers have consistently recognized that European unity makes sense only in the context of a dynamic, transatlantic relationship and have traditionally pursued a pro-NATO, pro-U.S. foreign policy.

Luxembourg is the site of the European Court of Justice, the European Court of Auditors, European Investment Bank, and other vital EU organs. The Secretariat of the European Parliament is located in Luxembourg, but the Parliament usually meets in nearby Strasbourg. Luxembourg will hold the EU Presidency in the first half of 2005.