Colorectal cancer is the second leading cause of cancer-related deaths in Western countries. Approximately 35% of patients will have metastatic disease at diagnosis, and an additional 25% of patients with resected stage II/III disease will develop recurrence. In approximately 30% of patients, metastatic disease will be restricted to a single organ, with the liver and lungs accounting for the majority of single organ-site metastases. In recent years, aggressive surgical resection of pulmonary metastases has become increasingly common with the recognition that this offers the best chance of long-term cure despite recent chemotherapeutic advances. Unfortunately, relapse after pulmonary resection remains approximately 70% despite advances in imaging and surgical technique. This review examines prognostic factors that influence survival after resection and repeat resection of pulmonary colorectal metastases and examines the impact of lymph node metastases, chemotherapy, and hepatic metastases on outcome. Pathologic markers that might determine outcome and current literature, which consists mainly of retrospective institutional reports, is reviewed.