Study objective: To assess the utilization of venous thromboembolism (VTE) prophylaxis in a medical-surgical ICU, Design: Prospective cohort study, Setting: A closed (mandatory critical care consult) medical-surgical ICU of a large community teaching hospital, Interventions: The medical records of consecutive medical-surgical ICU admissions were evaluated by a single investigator during a 3-month period, Risk factors for VTE and the type and timing of VTE prophylaxis were recorded, Measurements and results: Of 308 admissions evaluated, 209 were included in the study, VTE prophylaxis was administered within the first 24 h of ICU admission to 179 of the 209 study patients or 86%, Fifty-three percent (n=111) were surgical patients and 47% (n=98) were medical patients, The study patients had an average of 4.4 risk factors for VTE. Thirty study patients (14%) did not receive VTE prophylaxis, Conclusion: Eighty-sir percent of the medical-surgical patients included in this study received VTE prophylaxis, The utilization of VTE prophylaxis described in this study is higher compared to previously published data, The nature of physician coverage in our medical-surgical ICU (closed unit), consistent practice patterns of a designated ICU staff, and a continuing medical education program involving VTE prophylaxis are the factors believed to be responsible for these results.