David Usher is a career diplomat with the Government of Canada. He has a BA Hons. [History], Carleton University, Ottawa, 1979; a B.Ed., University of Ottawa, Ottawa, 1980; and M.Ed., University of Toronto, Toronto 1986).

Prior to joining the Public Service in 1991, David worked in the field of development in Nigeria, Malawi, Haiti and the Philippines. In 1991 he joined the Canadian Department of External Affairs and International Trade as a Trade Commissioner. From 1994 to 1997 he served as Second Secretary in the Canadian Embassy in Turkey. In 2001 he became Counsellor at the Canadian Permanent Mission to the World Trade Organization, in Geneva. From 2004 to 2008 he was Director of the Trade Controls Policy Division and later Director of the Softwood Lumber Controls Division. From 2008 to 2009, he was Senior Departmental Advisor in the Office of the Minister of International Trade. From 2009 to 2012 he served as Minister-Counsellor and Deputy Permanent Representative at the Canadian Permanent Mission to the OECD in Paris. From 2012 to 2015 he was the Canadian Ambassador to Ethiopia, Djibouti and the African Union. From 2015 to 2018 he was a Director General, Trade Negotiations in Global Affairs Canada dealing with a wide range of trade policy issues. In late 2018 he assumed new responsibilities as Canadian Ambassador to Argentina and Paraguay. Returning to Canada in October 2021, David began his latest assignment as Acting Consul General at the Consulate General of Canada in Chicago in January 2022.

He is married and the father of twin daughters.