Krister Bykvist is Tutor and Fellow in Philosophy at Jesus College, Oxford. His primary area of research is ethics. He has published articles on time-partiality, consequentialism, and the notion of alternative actions. He is currently working on a book about prudence and preference change across time.

John Broome is White's Professor of Moral Philosophy at the University of Oxford. He was previously Professor of Philosophy at the University of St Andrews and Professor of Economics at the University of Bristol. His books include Weighing Goods (Blackwell, 1991), Ethics Out of Economics (Cambridge University Press, 1999), and Weighing Lives, (Oxford University Press, 2004).

Tyler Cowen is Holbert C. Harris Professor of Economics at George Mason University. He is director of the James M. Buchanan Center for Political Economy and the Mercatus Center. His books include Creative Destruction: How Globalization Is Changing the World's Cultures, Princeton University Press 2004. His writings on philosophy have been published in Ethics and Philosophy and Public Affairs. Please address correspondence to tcowen@gmu.edu, Tyler Cowen, Center for Study of Public Choice, George Mason University, Fairfax, VA 22030.

Roger Crisp is Uehiro Fellow and Tutor in Philosophy at St Anne's College, Oxford. He is author of Mill on Utilitarianism (Routledge 1997) and Reasons and the Good (Oxford University Press, forthcoming).

Marc Fleurbaey is research director at CNRS-CERSES (Univ. Paris 5), a Lachmann Fellow at the London School of Economics and a member of the Institut d'Economie Publique (Marseilles). Most of his work is about normative issues in economics, specifically social choice and distributive justice: fairness and inequality, redistribution policies, and egalitarianism.

Nils Holtug received his Ph.D. from the University of Copenhagen in 1995. He is currently an Associate Professor at the Philosophy Section, Department of Media, Cognition and Communication, University of Copenhagen. His research focus is on distributive justice (in particular, egalitarianism and prioritarianism), multiculturalism, welfare, population ethics, and personal identity. Recent publications include: Egalitarianism: New Essays on the Nature and Value of Equality, Clarendon Press 2007 (co-edited with Kasper Lippert-Rasmussen), “Person-affecting Moralities,” in J. Ryberg and T. Tännsjö (eds.), The Repugnant Conclusion: Essays on Population Ethics, Kluwer Academic Publishers 2004, and “Welfarism – the Very Idea,” Utilitas 15 (2), 2003

Nien-hê Hsieh is an assistant professor in the Legal Studies and Business Ethics Department at the Wharton School, University of Pennsylvania. Current topics of research include the ethics of global assistance, work and authority, and incommensurable values. He has published in European Journal of the History of Economic Thought, Journal of Political Philosophy, Social Theory and Practice, and Utilitas. Email: nhsieh@wharton.upenn.edu

Liam Murphy is Professor of Law and Philosophy at New York University. He works on legal, moral, and political philosophy. His most recent book is The Myth of Ownership: Taxes and Justice (Oxford University Press 2002) (with Thomas Nagel).

Mozaffar Qizilbash is Professor of Politics, Economics, and Philosophy in the Department of Economics and Related Studies and the School of Politics, Economics, and Philosophy at the University of York. He works on a range of topics at the borderline of economics and philosophy and development economics most of which relate to well-being. He is currently editor-at-large of the Human Development and Capability Association and an editor of the Journal of Human Development.

Jack J. Vromen is associate Professor of Philosophy of Economics and managing director of EIPE (Erasmus Institute for Philosophy and Economics) at Erasmus University Rotterdam. His current research focuses on philosophical and conceptual aspects of attempts to connect economic theorizing with evolution and evolutionary theory.