Imatinib mesylate has recently been introduced as an important therapeutic option in chronic myeloid leukemia but its precise role in the management of chronic myeloid leukemia remains to be defined. A risk assessment score for the outcome after allogeneic stem cell transplantation that involves five prognostic features (age, disease stage, donor type, donor–recipient gender combination, and the interval from diagnosis to transplant) has recently been validated and applied to newly diagnosed patients. At present, it is unclear whether this or other prognostic indices can be usefully applied to patients who receive imatinib from diagnosis. From the current data, it would appear that cytogenetic remissions can be achieved in a significant majority of patients, but not all patients respond to imatinib, and some have developed resistance. Furthermore, the durability of the responses remains unknown. For now, the only curative option remains allogeneic stem cell transplantation, and this treatment should continue to be offered to young patients with suitable donors.