David has worked since the early 1980s on public health efforts, specializing in tobacco issues and focusing on how policy measures can impact population health.

He has played a key role in Canadian efforts on, among other things, tobacco taxation, advertising restrictions, package labelling, environmental tobacco smoke, smoking cessation, litigation and product regulation. He has also been active on a similar range of global issues, working with bodies such as the World Health Organization, World Bank, Pan American Health Organization and numerous governments, foundations and law firms.

In pursuing his interest in the interaction of law and economics as a determinant of public health, he has spent much time in recent years on the changing landscape of harm reduction products. This involves recognizing that there is a vast difference in risks associated with nicotine intake depending upon the delivery system, and that harm reduction principles have enormous potential to end the epidemic of smoking-caused death and disease.

He has been widely published in peer-reviewed scientific and legal journals as well as having authored work for major national and international health and social service organizations. He has spoken at conferences in numerous cities around the world, been a frequent guest on major media in Canada and other countries and testified before parliamentary committees in Canada and elsewhere, and before both Senate and House committees in the United States. He has received various awards for his work, including a ‘Public Health Hero’ lifetime achievement award from the Pan-American Health Organization.

David has also been actively involved in a wide range of other issues though funding and mentoring, and is the recipient of the Outstanding Individual Philanthropist award in Ottawa for 2016.