Lung cancer is a disease of older persons. It is the most common cause of cancer death in men and women in the United States. A comprehensive evaluation of medical comorbidities and functional status is important in all patients but perhaps more so in older adults, and it should be included in the assessment of older patients who have lung cancer. Age, per se, should not be a limiting factor to treatment, because a large body of evidence demonstrates that fit older patients who have lung cancer can safely undergo the same treatments as their younger counterparts with equally good results.