1989-93, Director, Policy Planning, Ministry of Foreign Affairs, France; Ambassador to Western European Union; Chairman, French Institute of Higher Defence Studies. 2000-08, Undersecretary-General, United Nations: longest tenure as head; led biggest expansion of peacekeeping. 2012, Deputy Joint Special Envoy to Syria. Former Director, Center for International Conflict Resolution, Columbia University. 2014-2017, President and Chief Executive Officer, International Crisis Group. 2018- 2020, Senior Adviser, Centre for Humanitarian Dialogue, Geneva. 2021 to present Arnold Salzman Professor of Practice, Director of the Kent Program on Conflict Resolution, School of International and Public Affairs, Columbia University. Chairman of the Scientific Committee of the Institute of Higher National Defense Studies, Paris. Member of the Board, Carnegie Corporation. Member of Secretary-General’s Advisory Board on Mediation, United Nations. Member of the board, SIPRI. Distinguished Fellow, Brookings Institution. Member, European Council on Foreign Relations. Author: End of the Nation State (1993); The Fog of Peace (2015); Le Premier XXIème Siècle, de la Globalisation à l' Emiettement, 2021. Recipient: Officier de la Légion d'Honneur; Commander's Cross, German Order of Merit.