Trials in advanced non-small cell lung cancer patients have shown that at least 10 drugs have objective response rates of > or =15% in phase II studies. These responses are reflected both in symptomatic benefit and in improved survival relative to best supportive care. However, greater benefit occurs in stage III patients when chemotherapy precedes either surgery or irradiation, which enhances both survival duration and curability. Combination chemotherapy should be considered part of the treatment of all ambulatory patients with non-small cell lung cancer and can be a cost-effective use of health care resources. New agents and the possibility of combining chemotherapy with new treatment modalities offer opportunities for further improvement.