Dr. Clyde F. Barker, as Chairman, guided the Department of Surgery from 1984 to 2001. During that time the Department flourished both from an academic and financial perspective. The faculty more than doubled in size and the department consistently ranked in the top 10 in NIH funding. The vast majority of individuals finishing their HUP residency or fellowship programs during Dr. Barker’s tenure have gone on to academic positions. Nine of them have become chairs of departments of surgery in US medical schools, and 30 others division chiefs. Dr. Barker's numerous recognitions include the presidency and the medallion for scientific achievement of the American Surgical Association, the presidency and the Pioneer Award of the American Society of Transplant Surgeons, and the Sheen Award of the American College of Surgeons. He has been elected to memberships in the Institute of Medicine of the National Academy of Sciences, the American Philosophical Society (Vice President, 2005-2011) and the American Academy of Arts and Sciences.

His clinical interests are focused in transplantation and vascular surgery. His research interests are transplantation biology and diabetes. His research has been funded through NIH grants since 1974, including a MERIT grant from 1987 to 1995. He has been and continues to be a mentor and role model for a generation of surgeons.

Dr. Barker's memberships in Scientific Societies include the American Surgical Association (President, 1996-97); Society of University Surgeons, The Society of Clinical Surgery, Halsted Society (President, 1986-87); the Society for Vascular Surgery, the American Society of Transplant Surgeons (President, 1992); the International Surgical Group (President, 1994-94). He is also a member of the Institute of Medicine of the National Academy of Sciences, the Association of American Physicians, the American Academy of Arts and Sciences, the American Philosophical Society, and the International Transplantation Society. He has served on the editorial boards of Transplantation, Journal of the American College of Surgeons, Annals of Surgery, Surgery, Archives of Surgery, and Diabetes.

He has authored more than 400 scientific papers. He is recognized as one of the leading investigators in the transplant field in the United States. He initiated HUP's transplant program in 1966 and is credited with building it into the largest and most successful program in the area.

In 2009 Dr. Barker received the Lifetime Achievement Award of the Society of University Surgeons and the Thomas E. Starzl Prize in Surgery and Immunology of the Starzl Institute at the University of Pittsburgh.