William Fisher is a Visiting Fellow in the College of Diplomacy at the Australian National University. He was formerly a senior officer of the Department of Foreign Affairs and Trade. He served most recently as the Australian Ambassador for Counter-Terrorism (2013-14), the Prime Minister's Special Envoy to the Francophone States (2011-2013), High Commissioner to Canada (2005-2008), Ambassador to France (2000-2005) and Algeria, Morocco and Mauritania, Ambassador to Thailand (1997-2000), Ambassador to Israel (1990-94), and previously as Charge d'Affaires to Iran, Consul General Honolulu and Micronesia, Consul General to the New Hebrides, Consul General in New Caledonia, with earlier postings also in the Australian Embassy in Laos and in the Australian Missions to the United Nations in Geneva and in New York.

In Canberra Mr Fisher held a number of senior positions in the Department of Foreign Affairs, including as Head of the Africa and Middle East Division, the Consular and Security Division, the International Organisations and Legal Division, and Head of the Defence Branch of the Department of the Prime Minister and Cabinet.