Varying institutional definitions and degrees of surveillance limit awareness of the true incidence of posttraumatic pulmonary complications. Prospective review with standardized definitions of 25 categories of pulmonary complications was applied to a university level I trauma service over 3 years to establish the true incidence. Potential injury-related predictors of individual complications were determined using multiple logistic regression analysis and adjusted odds ratios were calculated, thereby controlling for the effect of other covariants. Significance was attributed to p < 0.05. Of 3289 patients meeting MTOS criteria, pulmonary complications occurred in 368 (11.2%). Pulmonary complications account for one third of all disease complications. Significant associations with pneumonia included age, the presence of shock on admission, significant head injury, and surgery to the head and chest. Significant risk for atelectasis occurred in patients with blunt injury mechanism, ISS > 16, shock on admission, and severe head injury. Risks for development of respiratory failure included age > 55 years, the mechanism of "pedestrian struck", and the presence of significant head injury. Risk factors for ARDS included surgery to the head and a Trauma Score < 13 on arrival. Significant predictors for pulmonary embolism included ISS > 16, shock on admission, and extremity and pelvis injuries. The true incidence of pulmonary complications is established with this kind of analysis and focuses attention on (1) groups at high risk for developing complications, (2) groups for which current therapeutic modalities are still ineffective, and (3) defining the need to refocus on prospective research rather than ineffective processes of care.