Sufyan Droubi is a Lecturer in International Law at the University of Dundee Jean d'Aspremont is Professor of International Law at Sciences Po Paris and the University of Manchester
'Overall, the book is a great source for anyone interested in the general theoretical issues of customary international law, as well as those who have an interest in narrower questions on the role that international organisations and non-state actors have at different stages of the making of customary international law.' Journal of International Law of Peace and Armed Conflict -- .