Forty patients with N2 non-small-cell lung cancer (stage IIIA), as determined by mediastinoscopy, were entered into a preoperative neoadjuvant study of chemotherapy (platinum, 5-fluorouracil, vinblastine) and accelerated radiotherapy (150 cGy twice per day for 7 days) for two cycles. Surgical resection was then performed and followed up with an additional cycle of chemotherapy and radiotherapy. All patients completed preoperative therapy. A major clinical response was seen in 87% of patients. Thirty-five patients underwent resection (one preoperative death, one refused operation, one had deterioration of pulmonary function, and two had pleural metastases). Operative mortality rate was 5.7% (2/35). Sixty percent of patients had no complications. Major complications included pulmonary emboli (three), pneumonia (two), and myocardial infarction (one). Down-staging was seen in 46% of patients, with two patients (5.7%) having no evidence of tumor in the specimen, five patients having sterilization of all lymph nodes, and nine patients having sterilization of mediastinal nodes but positive N1 nodes. Median survival of 40 patients was 28 months, with a projected 5-year survival of 43%. Patients with downstaged disease had statistically significant improved survival compared with patients whose disease was not downstaged.