The 1944 systemic-to-pulmonary shunt saved the lives of numerous children with cyanotic congenital heart defects — especially tetralogy of Fallot — by surgically creating a shortcut that increased pulmonary blood flow. It was the result of an unequally recognized collaboration: Alfred Blalock performed the surgery, Helen Taussig conceived the clinical idea, and Vivien Thomas — an African American laboratory technician without a medical degree — developed the experimental model and was present in the operating room guiding the surgeon. The recovery of Thomas's name in the history of this milestone is one of the best-known examples of correcting scientific credit in 20th-century medicine.