Plain radiographs and computed tomography are the imaging techniques of most value in staging patients with lung cancer. Although each can provide significant anatomic information regarding the extent of intrathoracic tumor, it must be realized that these techniques have limited accuracy for diagnosing the presence of chest wall or mediastinal invasion by tumor and the presence of mediastinal node metastases; however, the appropriate use of imaging studies, including magnetic resonance imaging, is valuable in determining whether invasive diagnostic procedures are necessary for staging, which invasive procedure should be performed, and how these procedures are guided and eventual surgery should be planned.