He also gives frequent lectures at the Graduate School of Medicine. Until 2013, he taught at the Faculty of Law of the University of Sydney, and held visiting positions inter alia at the University of Hong Kong, the University of Ottawa, and Renmin Law School of China in Beijing. He also continues to teach and research at law schools in China and East Asia on a regular basis. Recent overseas teaching engagements include courses by Duke University, Seoul National University, and Wuhan University. Stefan is further active as a consultant, and is a legal practitioner and member of the World Commission on Environmental Law. He was educated at the Universities of Sydney, Frankfurt, Mainz, and at Harvard Law School, and holds degrees in law, philosophy, and political science.