Francesco Calogero, professor of physics at the University of Rome "La Sapienza", spoke in the Main Lecture Hall on 26 February on issues related to nuclear weapons development and control. Calogero serves as Chairman of the Pugwash Council (1997-2002). Pugwash received the Nobel Prize for Peace in 1995. In his hour-long lecture, Calogero noted that the number of nuclear warheads has declined from a peak of 70,000 in 1986 to about 30,000 today. He also noted that the post Cold War political environment, the enlargement of NATO (the North Atlantic Treaty Organization), and efforts to develop a ballistic missile defense, particularly on the part of the United States, continue to define developments in nuclear weaponry and control. Calogero observed that in his opinion the only current role for nuclear weapons is to deter the deployment of nuclear weapons and that ultimately such weapons will be eliminated.