In September 1971, Iceland issued regulations extending its fisheries limits from 12 to 50 nautical miles. The United Kingdom (UK) and the Federal Republic of German (West Germany) strongly protested Iceland's action and each instituted proceedings against Iceland in the International Court of Justice (ICJ) claiming that the ICJ had jurisdiction over the dispute and that Iceland's action violates international law. In August 1972, the UK and West Germany each obtained an interim order from the Court indicating that, pending the Court's final decision, Iceland should not enforce its new limits against UK or West German vessels fishing in the disputed waters. In February 1973 the ICJ handed down judgments holding that it had jurisdiction over the two disputes and would proceed to adjudicate the merits. This article, published pending the courts final decision in the matter, discusses: (1) the background and diplomatic history of the dispute; (2) the legal issues involved, including the validity and effect of the ICJ's Interim Order, the Court's jurisdiction over the dispute, and the legality of Iceland's 50 mile fisheries' limits; (3) other aspects of the dispute, including the interrelation of the ICJ case and the then impending Law of the Sea Conference negotiations, the role of international adjudication, and the role of unilateral state action in international change; and (4) the prospects for the outcome of the ICJ case and settlement of the dispute. The controversy is interesting as illustrating: (1) the nature of the claims and interests at stake in fisheries disputes, which are an important and recurring source of international conflict; (2) the potential role and limitations of international law in adjusting such fisheries' controversies; (3) the pressures on international law from increasing attempts by coastal states to extend their jurisdiction over their coastal waters; and (4) interesting and important legal issues respecting the law of international agreements, the nature of customary law, the role of the ICJ, the strategy and tactics of international legal controversy, and the workings of the international legal process.