Today’s most groundbreaking experiments in medicine—gene editing to correct inherited disorders, immunotherapies to cure cancer, molecularly engineered organs for human transplantation—stem from the strides of one visionary: Dr. E. Donnall Thomas.   In the last half of the twentieth century, Thomas himself discovered a cure for every marrow-based disease—like leukemia, lymphoma, and sickle-cell anemia—forever changing treatment for some of the deadliest illnesses. His feats were extraordinary, earning him a Nobel Prize, and the cascade of treatments he inspired have reshaped and will continue to reshape the practice of clinical medicine. Yet no one has ever written Thomas’s courageous story. Dr. Frederick R. Appelbaum, a member of Thomas’s research team, does so for the first time in Living Medicine: Don Thomas, Marrow Transplantation, and the Cell Therapy Revolution.   Bone marrow transplantation has now saved over a million lives, but when Thomas first had the idea, he was met with disbelief by the scientific community. Appelbaum, informed by decades in the field and personal connection with Thomas, tells us the secrets to Thomas’s success: his unique characteristics, how he created an effective team of researchers, and how he overcame the technical obstacles of marrow transplantation. Appelbaum tells a bigger story, too, of the scientific and societal implications of this achievement, which are critical for scientific and lay readers alike so that we all might be better informed of how far our medical progress has come and will go.