More than 150,00 patients a year present to their physicians with the diagnostic dilemma of a solitary pulmonary nodule (SPN) found either on chest radiography or chest CT. A thoughtful and timely workup of this finding is essential if lung cancer is to be recognized early and the chance for cure optimized. Based on the literature to date, recommendations are made for appropriate imaging modalities and diagnostic testing, as well as indications for obtaining preoperative tissue diagnosis for the patient with an SPN.