Theoretical physicist Sidney Coleman, professor at Harvard  University, died on 18 November at Cambridge, Mass., USA. He was 70.  Coleman first visited ICTP in 1983 as a tutor at the ICTP Summer  Workshop on Particle Physics. He came back in 1991 as the recipient  of the ICTP Dirac Medal 1990, and to lecture at the Summer School in  High Energy Physics and Cosmology.