In an International Community characterized by the weight of state sovereignty the interpretation of international norms (by states, International Organizations and judicial and arbitral bodies) is one of the key points of this legal order. State sovereignty conditions the creation and application of International Law as well as the settlement of disputes. That why the intervention of judicial and arbitral bodies acquire a great importance. This work contents a comprehensive and critic approach to international judicial and arbitral case law concerning interpretation of international norms and international institutions as well as to the way the International Court of Justice conceives access to its jurisdiction ant its exercise. So, conventional instruments and instruments of a statutory nature, customary norms, institutional norms of the United Nations, unilateral declarations, as well as procedural instruments, facts alleged and the exercise of the jurisdiction attributed to the International Court of Justice – in the way they have been interpreted by the Court – constitute the object of a work surely useful for persons involved in international practice, studies or teaching.