Rex Martin is a Professor of Philosophy at the University of Kansas. Martin earned his B.A. degree from Rice University in 1957 and his M.A. and Ph.D. from Columbia University, the latter in 1967. He also did post-graduate work at the University of Ediburgh, Scotland, from 1965 to 1966 in theology and philosophy.

Martin taught at Columbia University, Purdue University, and Lycoming College in Williamsport, Pennsylvania, before coming to Kansas in 1968. He was promoted to associate professor in 1970. Martin served as chairmain of the Department of Philosophy from 1972 to 1978.

Martin's research has been in the areas of political and legal philosophy, in particular rights, history of ethics and philosphy of history. Martin is the author of three books in these fields: Historical Explanation: Re-enactment and Practical Inference, Rawls and Rights, and A System of Rights.

In 1983, Martin received the Byron T. Shutz Award for Distinguished Teaching on Economic Systems. He was the first KU professor outside of business and economics to receive the award. Martin has also received the Higuchi Endowment Research Achievement Award in 1999 and Fulbright Research, National Endowment for Humanities, and Rockefeller Research Fellowships. He has held visiting teaching appointments at Mount Vernon College (Washington, D.C.), the University of Auckland (New Zealand), the Faculty of Law, University of Sydney (Australia), and the University of Helsinki (Finland).

Martin has also been a visiting research fellow at the Rockefeller Foundation Bellagio Study Center, in Italy (June 1980), at the School of Historical Studies at the Institute for Advanced Study, Princeton, Nj (Spring 1984), at the Centre for Ethics, Philosophy and Public Affairs at the University of St. Andrews, Scotland (Spring 1991), at St. Catherine's College, Oxford (as Chrestensen Fellow, during Trinity Term 1999), at Helsinki University (under a grant from the Academy of Finland, April/May 2000), and at the National Humanitites Center (2004-2005).

Martin has also been active in the International Association for Philosophy of Law and Social Philosophy (Ivr) and was a member of the Ivr Executive Committee (1991-2003) and Vice President (1995-2003). He served as President of the American Section of Ivr in 1993 until 1995. He also served as Chairman of the American Philosophical Association's Committee on Philosophy and Law (1992-1995).