Congenital malformations of the lung are a frequent cause of abnormal chest radiographs in neonates and young children as well as a common cause for recurrent pneumonia in older patients. Based on the mode of presentation and clinical findings along with an understanding of lung embryology, one can develop a thorough differential diagnosis that allows for the evaluation of the lesion in question. Appropriate management of the patient can then be undertaken with a minimum of diagnostic studies and without any delay in treatment.