Long-term second remissions were seen in 5/66 patients with all. Relapse was extramedullary in 2/5. Persistent, progressive marrow lymphocytosis preceded relapse in 4/5 patients and persistent marrow eosinophilia in 1/5. All 5 patients had had an unmaintained remission of at least 6 months prior to relapse, and responded the second time to drugs which were essentially the same as those used initially. We conclude that long-term second remissions may occur in all. Patients who relapse after 6 months or more of unmaintained remission should be treated with the drugs used in current initial induction regimens in hope of cure.