A high index of suspicion is required to consider the diagnosis of adult congenital lung disease because of the rarity of presentation in adulthood. The purpose of this article is to provide a framework for evaluation of these lesions and a guide to management. Adults may be asymptomatic, and the abnormality identified as an incidental imaging finding or the individual may present with symptoms of cough, hemoptysis, or recurrent pneumonia. The diagnosis may be readily apparent on computed tomography imaging because of a characteristic appearance, or the abnormality may require further evaluation for diagnosis with supplemental magnetic resonance imaging. Surgical resection provides a definitive diagnosis. The congenital lung malformation may be a solitary lesion or part of a complex group of abnormalities. A detailed review of all the components of the thorax is required to identify additional lesions. Management is typically surgical resection because of the propensity of these lesions to enlarge and to become infected as well as the potential risk for malignant transformation. Computed tomography surveillance may be appropriate for small asymptomatic lesions or lesions with either no or very low risk for developing malignancy.