Professor Dr. Kalayoğlu was born in Ankara in 1940. Kalayoğlu graduated from the Ankara University Faculty of Medicine in 1963 and served in the Department of General Surgery at Hacettepe University Medical Faculty. Between 1967 and 1968, he worked at Mount Sinai Medical School, Department of General Surgery, between 1968 and 1971, at the Pittsburg Children's Hospital Department of Pediatric Surgery. Dr. Kalayoğlu received his Associate Professor degree in 1972 at Hacettepe University Faculty of Medicine and Professor degree in 1977. Between 1981-1983, he worked with Professor Thomas Starzl, pioneer in liver transplantation, at the University of Pittsburg Transplantation Department. In 1983, Kalayoğlu started the Liver Transplantation Program at the University of Wisconsin. Since 1988, he has been running the presidency of this program. Kalayoğlu also received Associate Professor degree in 1986 and Professor degree in 1988 at the same university. He is also working as a Professor of organ transplantation at the University of Wisconsin in the United States. As of October 2, 2006, Dr. Kalayoğlu served as the head of the Department of Organ Transplantation, General Surgery and Pediatric Surgery at Memorial Şişli Hospital. Since March 2018, he has been working as the head of the Koç University Hospital Organ Transplantation Center.