Abstract: A study was done to compare trauma patient outcome at American College of Surgeons (ACS) Level l Trauma Centers with Emergency Medicine residency programs (EMRP+) to those without (EMRP−). Ten Level l Trauma Centers were reviewed from the ACS National Trauma Database (5 centers with and 5 without EM residency programs). Of 18,591 trauma patient records, 8679 were identified as EMRP−, and 9912 as EMRP+. After deleting incomplete data sets, 6621 EMRP− and 6150 EMRP+ records remained. Comparisons between patient age, gender, TRISS, complications, deaths, hospital, ICU and ventilator days, and numbers of burns, penetrating and blunt trauma were performed using t-test and chi-square analysis. Despite having a statistically significant older patient population, with more burn and penetrating trauma patients requiring longer ICU stays and longer ventilatory support (p < 0.0001), Emergency Medicine Residency program hospitals had a significantly lower complication rate (5.14% vs. 11.04%, respectively, p < 0.0001), death rate (4.704% vs. 5.479%, respectively, p = 0.0013), and shorter overall hospital stays (Mean 4.94 days, SD ± 8.74 vs. 6.35 days, SD ± 11.22, respectively, p < 0.0001) than EMRP− hospitals. The presence of Emergency Medicine residency programs at ACS Level I Trauma Centers is associated with improved trauma patient outcomes. [Copyright &y& Elsevier]