Chemotherapy for non-small cell lung cancer (NSCLC) is unsatisfactory, and the search for new active drugs has been relatively unsuccessful. Most polychemotherapy regimens in NSCLC include cisplatin with a vinca alkaloid or etoposide. Among the new agents tested in recent years, teniposide produced a 17% response rate in 42 evaluable patients, with a 21% response rate in untreated patients. The Lung Cancer Cooperative Group of the European Organization for Research and Treatment of Cancer has started a randomized trial comparing two different schedules of teniposide administration with and without cisplatin. This paper reports the preliminary findings for the initial 80 patients in this randomized study.