Dr Gully is a public health consultant and Adjunct Professor in the School of Population and Public Health, UBC. He is currently providing advice to the BC First Nations Health Authority and is on an expert panel advising Metro Vancouver on public health aspects of a planned waste to energy facility.
Dr Gully was Senior Medical Advisor to the Deputy Minister of Health Canada until the beginning of 2013, was the federal representative on the Public Health Network Council and was the Canadian representative on the Executive Board of the World Health Organization. Prior to September 2009 he was Deputy Coordinator for the United Nations System Influenza Coordination office and from 2006 until 2009 was Senior Advisor to the Assistant Director General, Health Security and Environment (HSE) at WHO.
From 2004 until 2006, Dr Gully was deputy chief public health officer for Canada in the Public Health Agency of Canada and had worked in Health Canada from 1990. Prior to 1990, Dr Gully worked in public health at the local and regional level in Canada and the UK.