André Nollkaemper is Dean and Professor of Public International Law of the Faculty of Law of the University of Amsterdam. He is member of the Royal Netherlands Academy of Arts and Sciences and the Institut de Droit International, was external Legal Advisor to the Minister of Foreign Affairs of the Netherlands (2010 – 2020) and President of the European Society of International Law (2014-2017) and has been visiting professor at the Graduate Institute of International and Development Studies in Geneva and the University of Oslo. He has published widely on questions of international law, with a particular focus on the law of international responsibility, the interaction between legal systems, international environmental law and protection of species.