This book provides a complete overview into the work of the International Court of Justice in the last twenty years. Since 1989, the author, a former Principal Legal Secretary to the International Court of Justice, contributed frequent articles on this subject to the British Yearbook of International Law continuing the work begun by Sir Gerald Fitzmaurice in 1950. This work brings together these articles in one place for the first time, with extensive cross-references, and a thorough index and tables, making it more accessible than ever. This collection addresses all of the areas of international law that the International Court of Justice has addressed with depth and nuance. The topics considered include general principles of law, sources of law, treaty interpretation, substantive issues such as the law of the sea, state sovereignty, and state responsibility, questions of jurisdiction and competence, and questions of the Court's procedure. A comprehensive work of incredible detail, this collection is essential reading for those studying the law and procedure of the International Court of Justice, and its role at the heart of the international legal system, as well as for practitioners appearing before the Court.