Director-Generalde: janvier 1994 à: janvier 1999
After education at Oxford and a brief period as an exchange Fellow in Moscow, Llewellyn Smith was a CERN Fellow from 1968 to 1970. After two years at SLAC, he returned to CERN during 1972-1974 as a staff member in the Theoretical Studies (TH) Division and became a member of the Experimental Committee for Super Proton-Synchrotron (SPSC) from 1973 to 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 1986 to 1993 he was a member of the CERN Scientific Policy Committee (SPC), 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. During his mandate, the LHC accelerator was approved (December 1994) and Japan and the United States became Observer States. He was suceeded by Luciano Maiani as CERN Director-General in January 1999.