The authors report their experience with 25 patients suffering from C.M.L. who underwent splenectomy in an early phase of the disease. There were no operative deaths; seven patients had postoperative complications, three of which required re-operation for intra-abdominal hemorrhage. The follow-up is still too short to permit definite conclusions, but the results so far obtained suggest that splenectomy is useful in reducing leukemic tissue, improving the quality of life, and potentially efficacious in delaying the onset of blastic transformation.