Executive Dean, College of Arts and Science, 2004-2007, Vanderbilt University

Professor and Director, Center for Constructive Approximation, 2001-present, Vanderbilt University

Distinguished Research Professor, 1986-2001, University of South Florida

Professor, 1976-1986, University of South Florida

Associate Professor, 1971-1976, University of South Florida

Assistant Professor, 1969-1971, University of South Florida

Post-Doctoral Researcher, 1968-1969, Imperial College, London

Assistant Professor, Summer 1968, University of Maryland