Locally advanced non-small-cell lung cancer is a heterogeneous group of diseases encompassing both stage IIIA and IIIB disease. The treatment options vary, including surgery, chemotherapy, neoadjuvant concurrent chemoradiation, definitive chemoradiation, radiation, and various combinations of the above. Optimal therapy for each patient group is controversial; however, previous trials have shown efficacy of various treatments for different stages. Surgery as initial therapy is beneficial for patients with stage T3, N1 or T3-4, N0-1 disease due to satellite lesions within the same lung. Chemotherapy should be used for diseases minimally involving the mediastinal lymph nodes, whereas concurrent induction chemoradiation is a good option for bulky nodal disease prior to planning a resection. Concurrent definitive chemoradiation or definitive radiation should be reserved for patients who are not candidates for a surgical resection. Most importantly, the treatment strategy for stage IIIA/IIIB disease should involve a multimodality approach individualized to the patient's disease stage, age, underlying medical conditions, and performance status.