Twenty-nine patients with metastatic sarcoma were treated with a combination of methyl CCNU and actinomycin D. Patients with adequate bone marrow reserve received methyl CCNU 100 mg/m2 orally on day 1 and actinomycin D 0.3 mg/m2/day intravenously for five days. Both drugs were repeated every four weeks. Patients with inadequate bone marrow reserve received methyl CCNU 75 mg/m2 and actinomycin D 0.2 mg/m2/day for five days. All patients had received prior chemotherapy and had progressive disease at the start of the study. There was one complete response in a patient with peritoneal mesothelioma which lasted 18 months and the patient is still alive at 38+ months. Ten patients had stable disease including three patients who had responses between 25% to 50%. No responses were seen in 18 patients. The median time to progression for patients with stable disease was five months and for those with progressive disease was two months (P = 0.001). The median survival for patients with stable disease was 20 months compared with three months for patients with progressive disease (P = 0.001). The combination was generally very well tolerated and myelosuppression was insignificant. However, with the dosages and schedule used in this study, the combination of methyl CCNU and actinomycin D does not appear to have significant activity in advanced soft tissue sarcomas. Further studies with this combination are indicated in patients with mesothelioma.