This collection of chapters provides the most comprehensive study of the theory and practice on the contribution of international organisations and non-State actors to the formation of customary international law. It offers new practical and theoretical perspectives on one of the most complex questions about the making of international law, namely the possibility that actors other than states contribute to the making of customary international law. Notwithstanding the completion by the International Law Commission of its work on the identification of customary international law, the making of ... More

This collection of chapters provides the most comprehensive study of the theory and practice on the contribution of international organisations and non-State actors to the formation of customary international law. It offers new practical and theoretical perspectives on one of the most complex questions about the making of international law, namely the possibility that actors other than states contribute to the making of customary international law. Notwithstanding the completion by the International Law Commission of its work on the identification of customary international law, the making of customary international law remains riddled with acute practical and theoretical controversies which have been left unresolved and which continue to be intensively debated in both practice and scholarship. Making extensively reference to the case-law of international law courts and tribunals as well as the practice of treaty-monitoring bodies while also engaging with the most recent scholarly work on customary international law, this new volume provides innovative tools and guidance to legal scholars, researchers in law, law students, lecturers in law, practitioners, legal advisers, judges, arbitrators, and counsels as well as tools to address contemporary questions of international law-making.