Caroline Millar (born 1958) is an Australian diplomat and public servant who is currently Ambassador to Belgium, Luxembourg, the European Union and NATO. She has previously served as the Deputy Secretary for National Security of the Department of the Prime Minister and Cabinet, Deputy Head of Mission of the Australian Embassy in Washington, D.C., the Permanent Representative to the United Nations in Geneva, and was briefly the acting-Head of Mission of the Australian Permanent Mission to the United Nations in New York.[1]