42 patients with progressive and advanced non-small cell lung cancer received chemotherapy comprising ifosfamide 1.5 g/m2, mesna 1.5 g/m2 and mitomycin 1.2 mg/m2 daily for 5 days. Only those patients with symptoms and progressive disease were selected for treatment. Partial response was achieved in 10 42 patients (23.8%) and stable disease in 25 42 (59.5%). The Karnofsky performance status (KP) improved in 10 42 patients (23.8%) and a subjective respiratory symptom score improved in 12 patients (28.6%). In addition 27 patients (64.3%) had stabilisation of both the KP and respiratory score following chemotherapy. These results indicate that the ifosfamide and mitomycin combination is active in non-small cell lung cancer in this selected group of patients with antitumour and symptom control activity.