Until additional multi-institutional, randomized, controlled trials provide evidence to the contrary, open lobectomy with mediastinal lymphadenectomy should be considered the gold standard for treating patients with stage I NSCLC with sufficient cardiopulmonary reserve, including older patients. It is the operation with which alternative pulmonary resections, including video-assisted thoracoscopic lobectomy and sublobar resection, should be compared. In treating stage I NSCLC patients, sublobar resection should be reserved for patients with inadequate physiologic reserve to tolerate lobectomy and for those enrolled in clinical trials.