Lung cancer remains the leading cause of cancer-related mortality in the United States. In 2002, approximately 170,000 new cases of lung cancer will be diagnosed, and approximately 160,000 deaths will occur. Eighty percent of cases of lung cancer are of the non-small cell type, and 30 to 35% will be Stage IIIA/B and are considered potentially curable. The standard of care in the United States for those patients with unresectable Stage IIIA/B and a good performance status (PS) is a combination of systemic chemotherapy and thoracic radiation therapy (TRT). What is not clear in the management of these patients is the optimal strategy to employ in the combined-modality approach, as well as the optimal chemotherapy and radiation therapy dose and schedule.