AbstractINTRODUCTION In the untreated state, patients with chronic myelogenous leukemia (CML) generally are asymptomatic and do not require urgent or intensive therapy. Resolution of the signs and symptoms of the disease using standard therapies is achievable without significant toxicity or risk to the patient. However, unlike acute myelogenous leukemia (AML), where true remissions can be obtained, in CML, despite attaining“hematologic”remission, persistence of the abnormal malignant clone as evidenced by the presence of the Philadelphia chromosome-positive (Ph+) cells is characteristic. Eventually all patients with CML, despite control of their disease in the chronic state, will enter a blastic or terminal phase resembling acute leukemia which, for the most part, is resistant to therapy. Patients with CML can expect a median survival of approximately 36-40 months (1) which has not changed appreciably in the last five decades. The recognition of this has led to the pursuit of more aggressive therapy using chemotherapy, immunotherapy, and chemoradiotherapy with marrow transplantation. This review focuses on the treatment of CML in the chronic phase, the use of aggressive therapy to obtain true remission and possible cure, and the therapeutic options available to patients who have entered the blastic phase.