and he completed his training in general and thoracic surgery at Rikshospitalet in Oslo.Semb defended his doctoral thesis at the University of Oslo in 1971 with the title: Cardiac Transplantation: An Experimental Study in Dogs (Figure 1A). 1 Christiaan Barnard was a co-author on two of the articles in Semb's doctoral thesis (Figure 1B). Before Barnard performed the first human heart transplantation in South Africa, Barnard and Semb had formed part of the kidney transplant team in 1966 under the leadership of David M. Hume at the Medical College of Virginia in Richmond, VA. Together with Hume, Semb published his first academic article in 1968 on allogenic lymphocytes in an experimental kidney model. 2 Before completion of his training in Oslo as a cardiac surgeon he did extensive experimental research on regulators of gastric mucosal flow. After his return to Rikshospitalet, he did clinical studies on the early version of the Hall-Kaster disc valve prosthesis.In 1984, Viking Olov Björk retired from his dual position in Stockholm, and Semb was recruited for his knowledge of heart transplantations and was appointed head of the Department of Cardiothoracic Surgery at the Karolinska Hospital as well as professor of Thoracic Surgery at the Karolinska Institute.