Richard Beardsworth is professor of international politics in the Department of International Politics, Aberystwyth University. His current interests lie in international political theory, global political responsibility, and a sustainable liberalism. His most recent book is Cosmopolitanism and International Relations Theory (2011). rib17@aber.ac.uk

Allen Buchanan is James B. Duke Professor of Philosophy and Professor of Law at Duke University and (annual) Visiting Professor of the Philosophy of International Law at the Dickson Poon School of Law, King's College London. Buchanan's research is in political philosophy, with a focus on international issues, and in bioethics, with a focus on the ethics of genetic interventions with human beings. He is the author of Marx and Justice: The Radical Critique of Liberalism (1982); Ethics, Efficiency, and the Market (1985); Deciding For Others (with Dan W. Brock, 1989); Secession: The Morality of Political Divorce From Fort Sumter to Lithuania and Quebec (1991); Justice, Legitimacy, and Self-Determination: Moral Foundations for International Law (2003); Human Rights, Legitimacy and the Use of Force (2010); Beyond Humanity? (2011); Better Than Human (2011); and The Heart of Human Rights (2013). allenb@duke.edu

Neta C. Crawford is professor of political science at Boston University. Her most recent book is Accountability for Killing: Moral Responsibility for Collateral Damage in America's Post-9/11 Wars (2013). Her most recent article is “War ‘In Our Name’ and the Responsibility to Protest: Ordinary Citizens, Civil Society, and Prospective Moral Responsibility,” in Midwest Studies in Philosophy. nccrawford@earthlink.net

Janina Dill is a departmental lecturer at the University of Oxford's Department of Politics and International Relations. She is also an associate director of the Oxford Institute for Ethics, Law, and Armed Conflict and the deputy director of the Oxford Programme on the Changing Character of War. Previously, she held the position of Junior Research Fellow at Oxford's Faculty of Law. Her first monograph, Legitimate Targets? Social Construction, International Law and US Bombing, appeared as part of the Cambridge Studies in International Relations series (2014). The book is based on her doctoral dissertation, which has won two academic awards: the Lord Bryce Prize for the Best Dissertation in International Relations/Comparative Studies and Oxford University's prize for an outstanding thesis in the area of international peace and understanding. janina.dill@politics.ox.ac.uk

Robert O. Keohane is professor of international affairs at the Woodrow Wilson School of Public and International Affairs, Princeton University. He is the author of After Hegemony: Cooperation and Discord in the World Political Economy (2005 [1984]) and Power and Governance in a Partially Globalized World (2002). He is the coauthor, with Joseph S. Nye, Jr., of Power and Interdependence (third edition, 2001) and, with Gary King and Sidney Verba, Designing Social Inquiry (1994). With Professor Buchanan he published “The Legitimacy of Global Governance Institutions” in Ethics & International Affairs (2006), and in the spring of 2015 their coauthored paper “Anti-Americanism and Anti-Interventionism in Arabic Twitter Discourses” will appear in Perspectives on Politics. Keohane has served as the editor of International Organization and is a past president of the American Political Science Association and the International Studies Association. He won the Grawemeyer Award for Ideas Improving World Order (1989) and the Johan Skytte Prize in Political Science, and is a member of the American Academy of Arts and Sciences and the National Academy of Sciences. rkeohane@princeton.edu

Shefa Siegel writes about resource governance and ethics, and has advised international organizations and development projects for over a decade, including the Earth Institute, United Nations, World Bank, and Natural Resources Canada. He has contributed articles on resources as well as religion and music to Haaretz, Sojourners, Yale Environment 360, and Americas Quarterly, and holds a PhD from the University of British Columbia. His previous essay for Ethics & International Affairs was “The Missing Ethics of Mining” (2013). shefayo@gmail.com

David Whetham is a senior lecturer in the Defence Studies Department of King's College London, based at the Joint Services Command and Staff College at the United Kingdom Defence Academy, where he coordinates or delivers the military ethics component of courses for between two and three thousand British and international officers a year. In spring 2011, Whetham was a visiting fellow at the Stockdale Center for Ethical Leadership, Annapolis; and in 2009 he was a visiting fellow with the Centre for Defence Leadership and Ethics at the Australian Defence College in Canberra. He is also a regular visiting lecturer in military ethics at the Baltic Defence College, the Military Academy in Belgrade, and for the Royal Brunei Armed Forces. Whetham is a vice president of the European Chapter of the International Society for Military Ethics. dwhetham@mac.com

John Williams is professor of international relations in the School of Government and International Affairs at Durham University, U.K. He coedited (with Cian O'Driscoll and Anthony F. Lang, Jr.) Just War: Authority, Tradition, and Practice (2013), and his most recent book, Ethics, Diversity, and World Politics: Saving Pluralism From Itself?, will be published in April 2015. Williams has published research on just war theory, English School theory, and the ethics of territorial borders in various journals, including the Review of International Studies, European Journal of International Relations, Geopolitics, and International Relations. j.c.williams@durham.ac.uk