André de Hoogh is a Senior Lecturer in International Law at the University of Groningen. He studied Law at the University of Nijmegen, with a specialisation in International Law. From 1990 to 1995 he conducted Ph.D. research at the same University. He did research at the United Nations International Law Commission in Geneva, the Max Planck Institute for Public and International Law in Heidelberg, and the Office of Legal Affairs in New York. During that period he published on jus cogens, obligations erga omnes, international crimes and State Responsibility. As from 1995 he was a Lecturer in International Law at Utrecht University. In that position he wrote on the right of self-determination, as well as on issues of complicity and non-recognition. In 1998 he was appointed Lecturer at the University of Groningen. In 1999 he served as a UN observer in East Timor during the referendum on the political future of the island.