William G. O’Neill is a lawyer specializing in humanitarian, human rights, and refugee law. He was senior advisor on human rights in the UN Mission in Kosovo, chief of the UN Human Rights Field Operation in Rwanda, and led the Legal Department of the UN/OAS Mission in Haiti. He has worked on judicial, police, and prison reform in Burundi, Liberia, Sierra Leone, South Sudan, Timor Leste, Nepal, and Bosnia-Herzegovina. He investigated mass killings in Afghanistan for the high commissioner for human rights. He also conducted an assessment of the human rights situation in Darfur and trained the UN's human rights monitors stationed there. At the request of the UN's Executive Committee on Peace and Security, he chaired a Task Force on Developing Rule of Law Strategies in Peace Operation. He has created and delivered courses on human rights, rule of law and peacekeeping for several peacekeeping training centers whose participants have included senior military, police and humanitarian officials from dozens of countries. He has published widely on rule of law, human rights, and peacekeeping, including, Kosovo: An Unfinished Peace (Lynne Reid Publishers, 2001) and Protecting Two Million Displaced: The Successes and Shortcomings of the African Union in Darfur (with Violette Cassis; Brookings, 2005).