Three patients with Hodgkin’s disease who developed severe pancytopenia terminating in acute leukemia (two patients) or preleukemia (one patient) are presented. Prior treatment consisted of radiation therapy alone in two patients, and radiation plus chemotherapy in the third. The only patient in whom chromosomal analysis was performed showed an abnormal chromosome. Therapeutic radiation exposure is thought to contribute to the development of leukemia in such patients. Leukemia is an uncommon complication of Hodgkin’s disease, but is being reported with increasing frequency. The rapid evolution of more aggressive modes of therapy makes it imperative that we seek more information regarding the incidence of this complication in order to achieve maximum therapeutic benefit for patients with Hodgkin’s disease.