This article focuses on the European Court of Justice (ECJ). In the EU system, control powers have been granted in particular to a supranational judicial body, the ECJ, which is a relatively small and isolated circle: less than 2,000 people currently work at the Court, located in Luxembourg. However, it has gained a major role in the daily lives of most European citizens, and has played a leading role in the integration process. The ECJ has decisively shaped the structure of the EU legal system and its relationships with national legal orders, and is now increasingly called upon to address delicate issues involving fundamental choices between economic freedom and social justice. But the context in which it operates has changed: EU competences have been substantially extended, as have the areas in which majority decision making is possible in the Council; the Parliament has gained new powers; and there are growing fears of an unequal distribution of the costs and benefits of integration in an enlarged and less-homogenous Union.