Ninety patients with stage-3 non-small cell lung cancer were given vindesine (3 mg/sq m) plus mitomycin (10 mg/sq m). Data on response are available for 84 adequately treated individuals (93 percent). For patients who had received no prior chemotherapy, the rate of major objective response was 36 percent (20/55). For previously treated patients the rate of major response was 17 percent (5/29). The drugs were routinely administered in the outpatient department without difficulty. Moderate or severe myelosuppression, neurotoxic, nephrotoxic, or pulmonary toxic effects, nausea, and vomiting occurred in less than 15 percent of all studied patients. Three-drug extravasation ulcerations occurred in 1,129 administrations of chemotherapy (0.3 percent). There were two treatment-related deaths, one from sepsis and one from the combination of mitomycin-induced pulmonary and renal toxic effects. The combination of vindesine plus mitomycin is an active, well-tolerated outpatient regimen for patients with non-small cell lung cancer who have not previously received chemotherapy. Further trials are warranted to compare this regimen to other active combinations and to use it as a component of a program of treatment using alternating regimens of chemotherapy.