Closson was previously President and Chief Executive Officer of University Health Network (UHN) in Toronto. Before joining UHN he worked in Victoria, BC as President and CEO of the Capital Health Region. Prior to that he was President and CEO at Sunnybrook Health Sciences Centre.

Closson obtained previous experience in health care consulting as an owner of Medicus Canada and as a Partner with KPMG.

He has government experience including with the Ontario Ministry of Health, the Ministry of Community and Social Services and the Management Board.

Currently, Closson is on the Board of Directors of the Canadian Foundation for Healthcare Improvement, Health Quality Ontario and LifeLabs. He co-chairs the Health Policy Advisory Panel for the C.D. Howe Institute. He is a volunteer advisor to entrepreneurs at MaRS.

A professional engineer, Closson earned an MBA from York University in Toronto and graduated from the University of Toronto with a Bachelor of Applied Science in Industrial Engineering.

He has received a number of career awards including being inducted into the Engineering Hall of Distinction at the University of Toronto and inducted as a Fellow of the Canadian Academy of Engineering. He has also received the Alumni Outstanding Public Contribution Award from the Schulich School of Business at York University.