The International Court of Justice (ICJ) as the principal judicial organ of the United Nations is neither a human rights court nor a criminal court. Because the jurisdiction ratione materiae of the ICJ is de facto unlimited and because violations of international human rights are considered to be violations of international obligations, the ICJ can deal also with international human rights law. Since only states which have locus standi before the Court, can claim a violation of human rights of either their own nationals occurring in a foreign state or of foreign nationals of a violating state. State complaints for the protection of own nationals in a foreign state are based on diplomatic protection, whereas such complaints for the protection of foreign nationals in a foreign state are based upon international human rights treaties or customary international law, especially obligations erga omnes. This article focuses on the contribution of judicial decisions of the ICJ as subsidiary means for the determination of rules of law in the field of international human rights law within the meaning of Art. 38 para. 1 lit. d) ICJ-Statute. It does so by analyzing relevant cases before the ICJ in recent years from various fields of human rights, especially relating to the right of peoples to self-determination, prohibition of genocide, prohibition of torture, and to human rights in conjunction with diplomatic protection, state immunity, and armed conflicts. Given that the ICJ is a universal court established for the peaceful settlement of disputes between states, and not a body specialized in human rights, the article also addresses the question of the interrelationship between the Court and specialized universal human rights control organs.