We treated 29 patients with chronic-phase and accelerated chronic myeloid leukemia (CML) with alpha-interferon in a dose of 2 mU/m2 given subcutaneously daily for 30 days and then three times per week. Most had received prior treatment. Three patients have had sustained hematologic and karyotypic remissions after a median of 22 months of treatment. Three further patients have had complete hematologic and partial karyotypic remissions. At a median follow-up of 48 months, the median survival has not been reached. This dose of alpha-interferon may induce sustained remissions even in pretreated patients and may prolong survival in CML.