Formerly, taught at University of Warwick, UK, Johns Hopkins University, Princeton University and Yale Law School. 2001-03, Assistant Secretary-General and Special Adviser to UN Secretary-General Kofi Annan, including strategic planning of Millennium Development Goals, outreach to international corporate sector and relations with Washington. Former Chair, Academic Council, UN System. Chair, UN Democracy Fund. Member, Council on Foreign Relations, New York. 2001, Fellow, American Academy of Arts and Sciences. 2009, American Philosophical Society. Author, including: Ways of War and Peace; Empires; Liberal Peace. UN Peacekeeping in Cambodia - UNTAC's Civil Mandate; Striking First - Preemption and Prevention in International Conflict (2008); numerous articles, chapters in books and occasional essays.