An examination of the legal framework of the EU internal market as established in the case law of the European Court of Justice, discussing in particular EC competition law, the free movement of goods, services, persons and capital and the evolution of the interpretation of the provisions. The 'State' has been retreating from direct intervention in economic life as more goods and services, the provision of which was once thought to be a 'public' responsibility, are delivered through market mechanisms. Given the need for consistent application of EC law in the internal market, a common core conception of public authority, shielded from the discipline of EC competition law, is needed. The resulting realignment of public and private functions and responsibilities is not a linear and coherent process, especially in light of the changing nature of the European legal integration project and the progressive incorporation of non-economic values in the Treaties.