Anatomical lung resection offers the best chance of cure for patients with localized lung cancer. Many people who have lung cancer have additional comorbidities, including other lung problems. Lung resection will affect our patient's pulmonary function. When evaluating patients for lung resection we use measures of pulmonary function, predictions of postoperative lung function and measures of exercise capacity to determine their short- and long-term risks from resection. This article attempts to relate the evidence that is available regarding the physiologic evaluation of lung-resection candidates to guidelines that have been developed to help us coordinate our assessment. Testing algorithms are provided from these guidelines. In addition, perioperative considerations and alternative surgical approaches are discussed.