Dr. Erwin Oechslin is Professor of Medicine at the University of Toronto and Director of the Adult Congenital Heart Disease (ACHD) Program, located at the Peter Munk Cardiac Centre, University Health Network, Toronto, Canada. After graduation from the University of Zurich, and completion of his cardiology training at the University Hospital in Zurich, he did a one-year fellowship in pediatric cardiology at the Hospital for Sick Children in Zurich and a 2-year fellowship in Adult Congenital Heart Disease at Toronto General Hospital / University of Toronto under the supervision of Dr. Gary Webb. In 1998, he returned to the University Hospital in Zurich and reorganized the Adult Congenital Heart Disease Clinic. He moved to Toronto, Canada, in 2006 and succeeded Dr. Gary Webb as Director of the Toronto ACHD Program. He resigned from this leadership position after 15 years in March 2021. He is Past-Chairman of the ESC WG on GUCH, Past-President of the ISACHD and of the CACH Network.