Jan Klabbers is professor of international organizations law at the University of Helsinki, and Director of the Academy of Finland Centre of Excellence in Global Governance Research. Prior to moving to Helsinki in 1996, he taught international law and EU law at the University of Amsterdam, where he also defended his doctoral thesis (with distinction). An award-winning teacher, he has held visiting professorships at the Graduate Institute of International Studies and Development (Geneva, 2008) and Hofstra Law School (New York, 2007).

Anne Peters is Professor of Public International Law and Constitutional Law at the University of Basel, a position she has held since 2001. She was visiting professor at Sciences Po, Paris in 2008/09. Prior to taking up the tenured post she was Assistant Professor at the Walther-Schucking-Institute of Public International Law at the Christian Albrechts University Kiel, where she obtained the Habilitation-qualification on the basis of her Habilitation-Thesis "Elemente einer Theorie der Verfassung Europas" (Elements of a Theory of the Constitution of Europe). Her research activities cover the field of general public international law, especially its constitutionalization, European constitutional law, constitutional theory and constitutional comparison and national and international human rights. She has published extensively on questions of supranational global governance and global constitutionalism.

Geir Ulfstein is professor of international law at the Department of Public and International Law, University of Oslo. He is dr. juris (Oslo 1995) and has acted as a judge in Norway. He has been Vice-Dean for Research and leader of the Committee to prepare Master of Law studies at the Law Faculty of the University of Oslo. He is deputy director of the Norwegian Branch of the International Law Association. He was director of the Norwegian Centre for Human Rights, University of Oslo, 2004-08. His research is on the law of the sea, international environmental law, human rights and the law of international institutions.

"...this coherent book whose well structured argument keeps the reader engaged throughout the almost 400 pages, and which helps put the whole constitutionalist debate in international law in clear perspective." --Antonios Tzanakopoulos, The Edinburgh Law Review