· Paul Pigott Professor of Computer Science and Electrical Engineering, Stanford University2009–
· Professor of Computer Science and Engineering, Massachusetts Institute of Technology1989–1991
· Senior Consultant Engineer, Systems Research Center, Digital Equipment Corporation1988–1993
· Senior Research Scientist, Systems Research Center, Digital Equipment Corporation1984–1988
· Senior Research Scientist, Xerox Palo Alto Research Center1982–1984
· PhD in Computer Science, Stanford University1976–
· Member of the Research Staff, Xerox Palo Alto Research Center1973–1982
· M.S. in Mathematics, California Institute of Technology1971–