· Professor and Charlotte B. and Roger C. Warren Chair of Computing, Georgia Institute of Technology2002–
· CTO, Hewlett-Packard2000–2002
· Vice President and General Manager of Information and Computer Sciences Research, Bell Communications Research (Bellcore) / Telcordia Technologies1995–2000
· Director of the Computer and Computation Research Division, National Science Foundation1989–1995
· Professor of Computer Science and Director of The Software Engineering Research Center, Purdue University1987–1995
· Director of the Software Test and Evaluation Project, US Department of Defense1981–1987
· Associate Professor of Information and Computer Science, Georgia Institute of Technology1976–1981
· Ph.D. in Information and Computer Science, Georgia Institute of Technology1972–
· Bachelor of Arts in Mathematics, University of St. Thomas1969–
· Visiting Professor, University of Padua
· Academic Appointment, University of Wisconsin-Milwaukee