Geoffrey Brennan trained originally as a public economist, but increasingly works in rational actor political theory. He was at the Australian National University for ten years, before he took up a Professorship in the Public Choice Center at Virgina Tech. In 1983, he returned to the ANU to become head of the Economics Department and in 1988 joined the Research School of Social Science, of which he was Director from 1991 to 1997. He is currently the Editor of Economics and Philosophy.
Philip Pettit teaches political theory and philosophy at Princeton University, where is William Nelson Cromwell Professor of Politics. Prior to taking up this post in 2002, he had been at the Australia National University, Canberra for many years. Irish by background and training, he has previously held positions at University College, Dublin; Trinity Hall, Cambridge; and Bradford University. His interests include the philosophy of cognitive and social science as well as moral and political theory.