Cancer of the lung which was almost unknown before 1930 is the most rapidly increasing cancer. It is certainly the cause of most cancer deaths in men. Women are not far behind, and it is said that cancer of the lung in women will surpass breast cancer in the next several years. This article will evaluate the suspect patient who visits his family doctor with one or more of the cardinal signs of cough, hemoptysis, chest pain, or shortness of breath and will establish the diagnosis by x-ray, bronchoscopy, cytology, and tissue biopsy. As the staging is evolved, treatment is dictated, which may take several forms: chemotherapy, radiologic, surgical, or a combination of any of the three. Probably more important is the symptomatic treatment of various side ailments. All of this must be accomplished with conscientious care and concern.