He held prior appointments as Professor of Medical Statistics and Population Health, Professor of Global Health, and Head of the School of Population Health at the University of Queensland from 2003 to 2012. Prior to joining the University, he worked at the World Health Organization (WHO) in Geneva, Switzerland for 22 years where he held a series of technical and senior managerial posts including Chief Epidemiologist in WHO’s Tobacco Control Program, Manager of WHO’s Program on Substance Abuse, Director of the Epidemiology and Burden of Disease Unit, and Senior Science Advisor to the Director-General.