Aerospace Engineer, Marshall Space Flight Center, NASA, Huntsville, AL (Summers 1961, 1962)
Instructor, Webster College, Webster Groves, MO (1966-1967)
Summer Employee, Oak Ridge National Laboratory, Oak Ridge, TN (Summer 1967)
Research Associate, University of Iowa, Iowa City, IA (1967-1968)
Research Assistant, University of St. Andrews, St. Andrews, Fife, Scotland (1968-1969)
Vacation Associate, Culham Laboratory, Abingdon, Berkshire, England (Summer 1969)
Leverhulme Visiting Fellow, University College of North Wales, Bangor, Caernarvonshire, Wales (1969-1970)
Visiting Scientist, Institut fur Plasmaphysik, 8046 Garching bei Munchen, Federal Republic of Germany (Summer 1970, August 1978)
Assistant Professor, College of William and Mary, Williamsburg, VA (1970-1975)
NASA-ASEE Summer Research Fellow, Langley Research Center, NASA, Hampton, VA (Summer 1971)
Summer Research, Langley Research Center, NASA, Hampton, VA (Summers 1972, 1973, 1974)
Visiting Staff Member, Los Alamos Scientific Laboratory, Los Alamos, NM (1974-1975, Summer 1976)
Associate Professor, College of William and Mary, Williamsburg, VA (1975-1977)
Staff Member, Los Alamos National Laboratory, Los Alamos, NM (1977-1984; 1992-2002)
SRC Senior Visiting Fellow, University of St. Andrews, St. Andrews, Fife, Scotland (July 1978; June 1980)
Adjunct Professor, University of New Mexico, Albuquerque, NM (Spring 1980; Spring 1982; Fall 1983)
Associate Group Leader, Los Alamos National Laboratory, Los Alamos, NM (1984-1987)
Group Leader, Los Alamos National Laboratory, Los Alamos, NM (1987-1992)
Professional Renewal Leave, University of California, San Diego, CA (Fall 1992)
Project Leader, Kurchatov Institute Project, Lab-to-Lab/MPC&A Program (1995-2002)
Fellow, Los Alamos National Laboratory, Los Alamos, NM (2002-Present)
223 refereed scientific publications, including 104 first-authored papers, as of 1 September 2002.
Scientific monograph, Theory of Space Plasma Microinstabilities, published by Cambridge University Press, 1993.
Editors' Citation for Excellence in Refereeing (Journal of Geophysical Research--Space Physics), 1993.
Editors' Citation for Excellence in Refereeing (Geophysical Research Letters), 1993.
Fellow, Los Alamos National Laboratory, 2002.