The treatment of acute nonlymphocytic leukemia involves a two stage approach. During the first stage, remission induction, cytotoxic drugs are administered to return hematopoiesis to normal. During the second stage, therapy is administered in an attempt to prolong the duration of remission. The clinical approaches and the problems incurred during these stages are not identical. At the time of diagnosis a decision must be made regarding whether or not the patient is likely to benefit from chemotherapy. If the answer is in the affirmative, then a decision must be made regarding the appropriate chemotherapeutic regimen. The optimal approach for the treatment of patients appears to vary depending on the age of the patient and whether or not there is a history of toxic exposure in the past. Overall remission rates vary from 40% to 85% depending upon the age of the patient and the patient's past history. Patients whose leukemia is induced into complete remission benefit from therapy administered after complete remission is attained. The optimal therapy, however, has not as yet been clearly defined. Conventional maintenance therapy appears to provide little benefit. On the other hand, the more intensive therapies are associated with substantial risk to the patient. The role of these modalities in the treatment of older patients is currently under investigation.