Material breach of a treaty gives a right to the aggrieved party to suspend or terminate it. This book traces the origins and evolution of the concept of material breach and responses thereto. It undertakes a content analysis thereof, thus clarifying the practical legal problems involved. The effects of breach of treaty are also examined. This book highlights the rules relating to application of the principle of termination or suspension of treaties for material breach in terms of limitations and conditions of their application, consequences, and the course and procedures for termination or suspension. Finally, competence to determine the existence of material breach is examined. The book addresses the settlement of disputes arising from claims of termination or suspension for breach. This work will be of interest to scholars as well as diplomats and practitioners of international law.