Ambassador Butler was appointed to lead UNSCOM on July 1, 1997. From 1992 to 1997, he was the Australian Ambassador and permanent representative to the United Nations. In 1994 he was elected President of the Economic and Social Council of the United Nations, in 1995 he chaired the Canberra Commission on the Elimination of Nuclear Weapons, and in 1996 he led the United Nations to adopt a comprehensive nuclear test ban treaty. He is now Diplomat in Residence at the Council on Foreign Relations.