University of California, San Diego (UCSD) March 1996-present
Executive Director, San Diego Supercomputer Center
San Diego Supercomputer Center* March 1996-present
Senior Fellow
San Diego Supercomputer Center 1995-1996
Executive Director
National Science Foundation 1993-1995
Deputy HPCC Coordinator
National Science Foundation 1988-1995
Program Officer for computational biology and databases
University of Wisconsin 1985-1988
Visiting Assistant Professor, Department of Statistics
Rochester Institute of Technology, Rochester, NY 1983-1985
Assistant Professor, Department of Mathematics