2002-present:  Professor, Departments of Government and Philosophy, University of Texas at Austin.

1995-2002:  Associate Professor, Departments of Government and Philosophy, University of Texas at Austin.

1988-1995:  Associate Professor, Department of Government, University of Texas at Austin.

1981-1988:  Assistant Professor, Department of Government, University of Texas at Austin.

1980-1981:  Acting Instructor, Departments of Political Science, Yale University.