This report is the result of an Eastern Cooperative Oncology Group (ECOG) study. Four hundred and 15 patients with inoperable metastatic malignant melanoma, excluding those with cutaneous metastases only, were randomized to one of three drug treatments: DTIC alone, methyl-CCNU alone, or the combination DTIC plus methyl-CCNU. Responses were seen in 14% of DTIC patients (19/127), 15% of methyl-CCNU patients (18/119) and 14% of DTIC plus methyl-CCNU patients (18/122). Duration of response was the same (14 weeks) for all three treatment groups. There was no difference among the treatments in achieving complete responses. Survival was improved significantly for responders (50 weeks) compared with nonresponders (15 weeks) regardless of treatment regimen. Toxicities were generally tolerable. DTIC caused significantly more gastrointestinal toxicity than methyl-CCNU. Methyl-CCNU caused significantly more bone marrow toxicity than DTIC. There were three drug-related deaths. All occurred in patients on combination DTIC plus methyl-CCNU. Important pretreatment characteristics that favor response are ambulatory status, female, less than 50 years old, no prior chemotherapy and no liver or brain metastases. Patients with favorable characteristics combinations had a 30% response rate, while those with unfavorable characteristic combinations had only a 9% response rate.