Fifty-three patients with advanced non-small cell lung cancer (NSCLC) were treated with alternating two-drug schedules cisplatin/vindesine and ifosfamide/mitomycin. Objective response (complete and partial response) was obtained in 31% (confidence limits 18.6-44%) of patients. The median duration of response was 26 weeks. The median survival was 25 weeks, with 24% of patients alive at 1 year. The toxicity was acceptable. The still poor antitumor activity of the chemotherapy schedules used and the lack of non-cross-resistance are factors that could explain the low antitumor activity of alternating chemotherapy.