· Adjunct Senior Research Scientist, Columbia University2005–2006
· Strategic Technology Research Advisor, Activium Inc.2000–2001
· Academic Visitor, Telcordia Technologies2000–
· Professor, Columbia University1998–
· Associate Professor, Columbia University1990–1997
· Academic Visitor, IBM Thomas J. Watson Research Center1990–
· Visiting Computer Scientist, Carnegie Mellon University Software Engineering Institute1986–
· PhD in Computer Science, Carnegie Mellon University1985–
· Assistant Professor, Columbia University1985–1989
· Project Director, Mindbank Inc.1983–
· Research Scientist, Siemens Corporate Research1981–1984
· MS, Computer Science, Carnegie Mellon University1980–
· Research Assistant, Carnegie Mellon University1979–1985
· ScB, Computer Science and Engineering, Massachusetts Institute of Technology1979–
· Division of Sponsored Research Staff Member, Massachusetts Institute of Technology1978–1979