OBJECTIVE: To determine the utility of routine chest radiographs (CXRs) in clinical decision-making in the intensive care unit (ICU). DESIGN: A prospective evaluation of CXRs performed in the ICU for a period of 6 months. A questionnaire was completed for each CXR performed, addressing the indication for the radiograph, whether it changed the patient's management, and how it did so. SETTING: A 14-bed medical-surgical ICU in a university-affiliated, tertiary care hospital. PATIENTS: A total of 645 CXRs were analyzed in 97 medical patients and 205 CXRs were analyzed in 101 surgical patients. RESULTS: Of the 645 CXRs performed in the medical patients, 127 (19.7%) led to one or more management changes. In the 66 surgical patients with an ICU stay <48 hours, 15.4% of routine CXRs changed management. In 35 surgical patients with an ICU stay > or = 48 hours, 26% of the 100 routine films changed management. In both the medical and surgical patients, the majority of changes were related to an adjustment of a medical device. CONCLUSIONS: Routine CXRs have some value in guiding management decisions in the ICU. Daily CXRs may not, however, be necessary for all patients.