1998-present: Professor, U. S. Naval Academy
2012: Visiting Professor, Max-Planck-Institut für Mathematik (Bonn, Germany) and Deutsches Elektronen-Synchrotron (Zeuthen, Germany). (On sabbatical leave from Naval Academy.)
2003-04: Visiting Professor, Max-Planck-Institut für Mathematik (Bonn, Germany) and Ruhr-Universität Bochum (Bochum, Germany). (On sabbatical leave from Naval Academy.)
1988-98: Assoc. Professor, U. S. Naval Academy
1984-88: Asst. Professor, U. S. Naval Academy
1981-82 and 1983-84: Instructor, Ohio State University
1982-83: Visiting Asst. Professor for Research, Memorial University of Newfoundland
1976-81: Graduate Teaching Assistant, Massachusetts Institute of Technology
Massachusetts Institute of Technology, 1976-81. Thesis "Cohomology Endomorphisms of Complex Flag Manifolds" under F. P. Peterson. Ph. D. Mathematics, June 1981.
Georgia Institute of Technology, 1973-76. B. S. Applied Mathematics (Highest Honor), June 1976.
Formerly topology of manifolds and fixed-point theory; more recently, algebraic combinatorics, multiple zeta values, and noncommutative algebra. See publication list.