Treaties and Subsequent Practice

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 It also includes two previously unpublished reports issued by the International Law Commission's Study Group on this topic.

1. Introduction ; PART 1: SUBSEQUENT PRACTICE AMONG THE DIFFERENT MEANS OF INTERPRETATION ; 2. Subsequent Agreements and Practice within the Vienna Convention ; 3. Keeping Subsequent Agreements and Practice in Their Right Limits ; 4. Subsequent Agreements and Practice from a Consensualist Perspective ; 5. Some Problems Arising in Connection with Subsequent Agreements and Practice ; PART 2: THE SIGNIFICANCE OF SUBSEQUENT PRACTICE IN DIFFERENT AREAS OF INTERNATIONAL LAW ; 6. Subsequent Practice, Practices and 'Family Resemblance': Towards Embedding Subsequent Practice in its Operative Milieu ; 7. The Relevance of Subsequent Agreements and Practice for Treaty Law to Date and in the Future ; 8. Subsequent Practice: The Battle over Interpretive Power ; 9. TBC ; PART 3: SUBSEQUENT PRACTICE BETWEEN INTERPRETATION, INFORMAL MODIFICATION, AND FORMAL AMENDMENT ; 10. Subsequent Agreements and Practice: Between Interpretation, Informal Modification, and Formal Amendment ; 11. Subsequent Practice Between Interpretation, Informal Modification, and Formal Amendment: A Comment ; 12. Law, Time and Change: The Self-Regulatory Function of Subsequent Practice ; PART 4: SUBSEQUENT PRACTICE AND THE DOMESTIC LEVEL ; 13. Domestic Constitutional Concerns with Respect to the Use of Subsequent Agreements and Practice at the International Level ; 14. Subsequent Agreements and Practice: Domestic Constitutions, Courts, and Legitimacy ; 15. Treaty Interpretation, Subsequent Agreements and Practice, and Domestic Constitutions ; PART 5: ILC STUDY GROUP ON TREATIES OVER TIME ; Introductory Report of the Study Group on Treaties over Time ; Second Report of the ILC Study Group on Treaties over Time