The Law of the European Integration stands as a sui generis system of rules, distinct from both International and national Law. The book examines in detail the evolution of the European Communities and the European Union. Furthermore, it analyzes the key features of institutional EU Law, as an autonomous system of rules, interacting with the Law of the Member States. The sources of EU Law, the creation of its rules as well as their enforcement at the EU and the national levels are thoroughly examined. Special emphasis is given to the problems of enforcement of EU Law in the Greek legal order. Finally, the book examines the system of judicial protection, as a necessary compound of the European Integration. The role of national judges (with an analysis of the relevant Greek case-law) and the procedure of the European Court of Justice are also scrutinized in the last part of the book.