After education at Oxford and a brief period as an exchange Fellow in Moscow, he was a CERN Fellow from 1968-1970. After two years at SLAC, he returned to CERN in 1972-1974 as a Staff Member in the Theoretical Studies Division and became a member of the Experimental Committee for Super Proton-Synchrotron (SPSC) from 1973-1976.
During the 1980s he was an Expert Advisor to two committees related to CERN: The Kendrew Committee (1984-1985) on UK Policy for Particle Physics and Membership of CERN, and the CERN Review (Abragam) Committee (1986-1987) on the future of CERN. From 19 86-1993 he was a member of the Scientific Policy Committee of CERN, serving as Chairman from 1990-1992.
In January 1994 he returned from Oxford, where he had spent the years 1974-1993, and succeeded Carlo Rubbia as Director-General of CERN.