The different starting points and uneven emphasis of historical accounts of transplantation [1] have tended to obscure the contributions to this field of some of the grand figures of French medicine and science. Clinical transplantation activity began in France within the first few years of the twentieth century when Jaboulay in Lyon [2] and others in France and Germany performed subhuman-primate-to-human kidney heterotransplantation [3][4][5]. In 1936, The Russian Yu Yu Voronoy of Kiev made the first known attempt at renal allotransplantation [6]. Visitors flocked to France in the early 1950s to learn firsthand from this experience, including John Merrill of Boston, as Hume described in the classical account of his own clinical trials at the Peter Bent Brigham Hospital [12]. The extensive discussion of the French experience by Hume was typical of this man whose awareness and acknowledgment of other people's work was noteworthy throughout his illustrious career. As important as these and later contributions of Kuss [13] and Hamburger [14] were, the scientific basis for transplantation in France went far deeper. The roots of histocompatibility research were nourished in France by Jean Dausset (Nobel Laureate 1980) [15]. In addition, George Mathe, the father of cell transplantation, was part of the Paris clique of the 1950s and early 1960s.The skills necessary to transplant the kidney (the only candidate organ until the 1960s) were applications of what were becoming conventional surgical practices after World War II. The vascular surgical technology came from the Frenchman Alexis Carrel [16] and had a pervasive effect on essentially all surgical specialties. Although Carrel understood that transplanted organs were not permanently accepted, the biologic specificity of the field of transplantation was defined by Medawar when he showed that rejection is an immunologic event [17,18]. In retrospect, every further development was a logical and inevitable step from this beginning. If rejection was in fact an immune reaction, what could be more logical than to protect the organ transplant by weakening the immune system? Medawar's conclusion about the nature of As Billingham, Brent, and Medawar (later referred to as the "holy trinity") meticulously annotated, the impetus and rationale for these experiments came originally from the observation by Owen [24] that freemartin cattle (the calf equivalents of human fraternal twins) were permanent hematopoietic chimeras if placental fusion and fetal cross-circulation had existed in utero. Burnet and Fenner [25] predicted that such chimerism and the ability to exchange other tissues could be induced by the kind of experiment eventually performed with Medawar by Billingham and Brent whose definition of tolerance was that it "is due to a primary central failure of the mechanism of the immunological reaction, and not to some intercession, at a peripheral level" [23].The surgical interest generated by the demonstration that tolerance could be acquired was quickly dampened when it w...