John L. Hennessy joined Stanford's faculty in 1977. He was named the Willard and Inez Kerr Bell Endowed Professor of Electrical Engineering and Computer Science in 1987.
From 1983 to 1993, Dr. Hennessy was director of the Computer System Laboratory, a research and teaching center operated by the Departments of Electrical Engineering and Computer Science that fosters research in computer systems design. He served as chair of computer science from 1994 to 1996 and, in 1996, was named dean of the School of Engineering.
In 1999 he was named provost, the university's chief academic and financial officer. As provost he continued his efforts to foster interdisciplinary activities in the biosciences and bioengineering. In October 2000 he was inaugurated as Stanford University's 10th president.