By focusing on the four freedoms of goods, services, persons, and capital, as well as citizenship rights, the book analyses how the Court's development of case law has ascribed a broad meaning to these freedoms. The constitutional status of this case law constrains policymaking at the European and member-state levels. Different case studies show how major pieces of EU legislation only partly codify case law. Judicialization is important in the EU. It also directly constrains member-state policies. Court rulings oriented towards individual disputes are difficult to translate into general policies-but if they have constitutional status they have to go through this process. Policy options are thereby withdrawn from majoritarian decision-making. As the Court cannot be overruled, short of a Treaty change, its case law casts a long shadow over policymaking in the European Union, undermining the legitimacy of this political order.