Fourty-three of 61 patients suffering from low-grade malignant non-Hodgkin's lymphomas according to the Kiel classification were subjected to an intermittent combination chemotherapy with chlorambucil and prednisone. In 12 of 35 evaluable patients a complete remission, in 14 of 35 a partial remission could be achieved. The mean remission time of patients with a complete remission exceeds 16 months, that of patients with a partial remission amounts to more than 8 months. In 9 of 35 cases a remission could not be achieved. As 10 of the 12 patients in whom a complete remission could be obtained are alive, the median survival time in cases of complete remission cannot yet be determined. The hematological toxicity was very low, nausea and lack of appetite were observed in 9 of 35 patients. Three of 35 treated and evaluable patients died, viz., 1 patient with a centroblastic-centrocytic lymphoma and 1 patient with a chronic lymphocytic leukemia died from the sequelae of progression during the chemotherapy of second choice according to the COP regimen. The third patient with a centroblastic-centrocytic lymphoma died from the sequelae of an intrahepatic cholestatic icterus, also during the chemotherapy of second choice according to the COP regimen. In the last-mentioned case, autopsy also confirmed a continuous complete remission of the centroblastic-centrocytic lymphoma.