Frontal chest radiographs are the principal diagnostic imaging study to detect, verify, or exclude acute thoracic injury after trauma, and they should be obtained as quickly as possible without compromising clinical assessment and resuscitation. Chest radiographs provide important information about potentially life-threatening conditions, such as tension pneumothorax, major hemothorax, and major arterial injury. In many patients, chest radiographs also provide helpful clues to the presence of such conditions as diaphragmatic rupture, pulmonary contusion/laceration, and tracheobronchial injury. In selected patients, computed tomography scans can supplement information provided by radiography, particularly for detection of mediastinal hemorrhage, aortic pseudoaneurysm, subtle pneumothorax, and delineation of complex pleuroparenchymal processes. On occasion, magnetic resonance imaging can be used to assess integrity of the hemidiaphragms and visceral herniation when other diagnostic studies are equivocal. We consider typical imaging findings associated with a variety of acute thoracic injuries, as well as the most appropriate use of available imaging techniques in different clinical scenarios.