Aims to provide a useful analytical tool and practical guidance on good treaty practice. It will be of interest to those working with treaties and treaty procedures in governments, international organisations, and legal practice, as well as legal academics and students wishing to gain insight into the realities of treaty practice.

This focused collection of essays on various aspects of the law of treaties does justice to its honoree, scholar and author Professor Bert E.W. Vierdag, on the occasion of his retirement as Professor of International Law and International Relations at the University of Amsterdam. Written by leading academics in the field as well as practitioners and former practitioners, the essays cover: - the alignment of treaties with more general sources doctrine, addressing such issues as conflicts between various types of treaties and the relationship between treaties and customary international law, and between treaties and domestic law; - the emergence of treaty norms through various ways and methods; and - the creation of treaty law in several branches of international law. This cohesive, focused, expert work will assist and appeal to both academics in the fields of public law and political science and professionals engaged in international negotiations and treaty-making.

Treaty-making constitutes the very basis of the international legal order and influences international relations. It channels the expression by States of consent to be bound and defines the commitments they enter into. However, the national procedures by which States express their consent to be bound vary considerably, depending on constitutional, legal, and political conditions which reflect the history of each country. The report, drawn up under the aegis of the Committee of Legal Advisers on Public International Law (CAHDI) of the Council of Europe, encompasses the practice of thirty-nine member States of this Organisation and a number of observer States. It provides comprehensive and up-to-date information about these States' means of expressing consent to be bound by a treaty. Furthermore, the analysis commissioned by the CAHDI from the British Institute of International and Comparative Law casts fresh light on this matter by inferring interesting considerations from the diversity of national procedures. With this report, the Council of Europe wishes to pursue its practical contribution to the development of international law, facilitating the mutual understanding of its member States and, thus, helping to build a stable and peaceful international community. La conclusion des traités constitue la base même de l'ordre juridique international et exerce une influence sur les relations internationales. Elle véhicule l'expression du consentement des Etats à être liés et définit les engagements qu'ils souscrivent. Cependant, les procédures nationales par lesquelles les Etats expriment leur consentement à être liés varient considérablement en fonction de facteurs constitutionnels, juridiques et politiques qui reflètent l'histoire même de chaque pays. Le présent rapport élaboré sous l'égide du Comité des Conseillers Juridiques sur le droit international public (CAHDI) du Conseil de l'Europe, expose la pratique de trente-neuf Etats membres de cette Organisation ainsi que d'un certain nombre d'Etats observateurs. Il fournit des informations complètes et à jour sur les moyens par lesquels ces Etats expriment leur consentement à être liés par un traité. En outre, l'analyse confiée par le CAHDI à l'Institut britannique de droit international et de droit comparé apporte un éclairage nouveau à ce domaine en tirant des enseignements intéressants de la diversité des procédures nationales. Par ce rapport, le Conseil de l'Europe souhaite poursuivre sa contribution pratique au développement du droit international, en facilitant la compréhension mutuelle de ses Etats membres et en contribuant ainsi à la construction d'une communauté internationale stable et pacifique.

The 1969 Vienna Convention on the Law of Treaties, regulating treaties between States, lies at the heart of international law. This commentary interprets the Conventiona (TM)s 85 articles clearly and precisely. It covers such major topics as reservations to treaties, their interpretation and the grounds for terminating a treaty, for instance breach. Emphasis is placed on the practice of States and tribunals and on academic writings. It contains further sections on customary international law and the Conventiona (TM)s history while providing up-to-date information on ratifications and reservations. This commentary is a must for practitioners and academics wishing to establish the meaning and scope of the provisions of the Vienna Convention on the Law of Treaties.

The Commentary on the Vienna Convention on the Law of Treaties provides an in-depth article-by-article analysis of all of the Vienna Convention’s provisions. Each provision’s analysis consists of (I) Purpose and Function of the Article, (II) Historical Background with Negotiating History, (III) Elements of the Article and finally (IV) Treaties of International Organizations. In short, the present Commentary contains a comprehensive legal analysis of all aspects of the international law of treaties. Furthermore, where the law of treaties reaches into other fields of international law, e.g. the law of state responsibility, the relevant interfaces are discussed and contextualized. With its focus on international practice, the Commentary is an invaluable reference for both academia and practitioners of international law.

Under the relevant rules of international law, treaties are interpreted in accordance with the ordinary meaning of the language they use, their object and purpose, and the intention of the drafters, but also in light of the subsequent practice of its parties. This subsequent practice can shed light on articles whose meaning is ambiguous and subsequent agreement can even alter the meaning of treaty provisions. At a time when many of the most important international treaties are more than fifty years old, subsequent practice plays an increasingly important role in their interpretation. Treaties and Subsequent Practice discusses the role and relevance of this subsequent practice in the process of dynamic treaty interpretation. The book provides a comprehensive treatment of this topic by eminent commentators, combining contributions which focus on practical cases with chapters examining the theoretical underpinnings of treaty interpretation. The concept of subsequent practice is situated in the more general context of treaty law and international law, looking at different cases and doctrinal questions to assess its policy dimensions. The book addresses the question of whether subsequent practice plays a more or less significant role in different areas of international law, and whether it can be employed as a partial substitute for formal treaty amendments. It also includes two previously unpublished reports issued by the International Law Commission's Study Group on this topic.