The European Court of Justice (abbr. ECJ), officially the Court of Justice (French: Cour de Justice), is the supreme court of the European Union (EU) in matters of European Union law. As a part of the Court of Justice of the European Union, it is tasked with interpreting EU law and ensuring its uniform application across all EU member states under Article 263 of the Treaty of the Functioning of the European Union (TFEU).
The Court was established in 1952, and is based in Luxembourg. It is composed of one judge per Member State – currently 27 – although it normally hears cases in panels of three, five or fifteen judges. The Court has been led by president Koen Lenaerts since 2015.