The majority of patients with lung cancer have disseminated disease at the time of presentation. For the minority of patients with disease localized to the chest, the concept of staging becomes particularly important because it has a major impact on the treatment plan. Guided by findings on the computed tomographic scan, mediastinoscopy remains the definitive invasive staging procedure to document unequivocally the involvement of the mediastinal lymph nodes. Equally as important is the documentation of absence of disease in contralateral lymph nodes. Patients with locally advanced non-small cell lung cancer, especially those with involvement of mediastinal lymph nodes (N2), are candidates for a multimodality approach to treatment involving either chemotherapy alone or in combination with radiation therapy. Surgical excision may be important in the management of these patients after an induction regimen. If surgical excision is performed, complete excision is the single most important factor. Postoperative adjuvant therapy may reduce the incidence of local recurrence but has not been shown to improve survival.