This chapter presents an overview of the current concepts in the diagnosis and treatment of carcinoma of the lung. Emphasis is placed on the increasing incidence, methods of detection, and diagnosis, and on the importance of staging before treatment. Best treatment recommendations are detailed by stage of disease and by presentation, with supporting evidence from institutional experience and the literature. Although surgical treatment is emphasized, other forms of management appropriate to the stage of the disease are included. The use of intraoperative irradiation to supplement surgery in the control of localized lung carcinoma is also described.