The largest of the three institutes under the UHN umbrella, the Toronto General Research Institute is the research arm of the Toronto General Hospital.

Toronto General Hospital is well-known for its excellent clinical care, and it is important to recognize that ground-breaking research efforts underlie our surgical and medical innovations. TGRI's research program encompasses research in cardiology, transplantation, immunology and autoimmunity, infectious diseases, tissue injury and diabetes. Building upon this work, scientists are able to develop improved methods of treatment and cure.

Organ transplants, cardiac pacemakers, novel therapies for endocrine and autoimmune disorders—all are based upon research carried out in TGRI laboratories and clinics.