The progression in understanding the biology of leukemia represents a remarkable bridging of clinical and laboratory science, which has provided much critical knowledge necessary for the design of curative protocols. Drs. Rachel Borson and Virgil Loeb, Jr., of the Division of Hematology/Oncology in the Department of Medicine at the Washington School of Medicine in St. Louis note advances that have led to increased survival in the present and research that holds even greater promise for the future.