Visitors to the Blalock Building at the Johns Hopkins University Medical Center are greeted by portraits of two great men. One, of renowned heart surgeon Alfred Blalock, speaks for itself. The other, of highschool graduate Vivien Thomas, is testimony to the incredible genius and determination of the first black man to hold a professional position at one of America"s premier medical institutions. Thomas"s dreams of attending medical school were dashed when the Depression hit. After spending some time as a carpenter"s apprentice, Thomas took what he expected to be a temporary job as a technician in Blalock"s lab. The two men soon became partners and together invented the field of cardiac surgery. Partners of the Heart is Thomas"s extraordinary autobiography. Trained in laboratory techniques by Alfred Blalock and Joseph W. Beard, Thomas remained Blalock"s principal technician and laboratory chief for the rest of Blalock"s distinguished career. Thomas very rapidly learned to perform surgery, to do chemical determinations, and to carry out physiologic studies. He became a phenomenal technician and was able to carry out complicated experimental cardiac operations totally unassisted and to devise new ones. In addition to telling Thomas"s life story, Partners of the Heart traces the beginnings of modern cardiac surgery, crucial investigations into the nature of shock, and Blalock"s methods of training surgeons.