Nicholas Chadi, MD, MPH, is currently a Clinical Assistant Professor at the University of Montreal. He is a clinician-scientist at Sainte-Justine University Hospital Centre where he is also the director of the substance use and addiction program as well as a co-director of the gender diversity clinic. Dr. Chadi completed medical school at McGill University and residency training in general pediatrics at the University of Montreal. He then completed subspecialty training in Adolescent Medicine as well as a fellowship in global journalism at the University of Toronto. He later obtained a Master of Public Health at Harvard University and was the first pediatrician in North America to complete a pediatric addiction medicine fellowship at Boston Childrens Hospital. His research focuses primarily on the prevention and treatment of mental health and substance use disorders, and specifically, tobacco, cannabis and vaping, among adolescents and young adults. He is the first author of the position statements on youth vaping from the Society for Adolescent Health and Medicine and the Canadian Paediatric Society.