A 46-month-old boy with juvenile chronic granulocytic leukemia was treated intensively with hydroxyurea, dimethyl myleran, cyclophosphamide, and total body irradiation. He then received a marrow transplant from an HL-A matched brother. Thirty-two months after the transplantation, he is hematologically normal and remains disease free on no-maintenance therapy. The successful outcome of this case suggests that a bone marrow transplant for any patient with a suitable histocompatible donor should be considered in the treatment of this disease.