Chapter 8 explores the essential institutional characteristics for maintaining homogeneity in the expanded internal market in the stages of application and implementation of the acquis. The analysis focusses on the institutional and procedural frameworks in the EU and the multilateral agreements, respectively, that are vested with the task of the uniform enforcement and application of the acquis in and outside the Union. The analysis is divided into two parts dealing with the centralising and decentralising dynamics, respectively. The former pertains to the centralised institutions and procedures for surveillance, enforcement and judicial protection in the EU and the multilateral agreements; and the latter to the procedural links between the international or supranational institutions, on the one hand, and national authorities and individuals, on the other.