Purpose To assess the impact of an emergency obstetric and neonatal simulation-based team training program (PRONTO) on process indicators and maternal and neonatal outcomes. Research Questions Does PRONTO training improve participating providers’ obstetric and neonatal emergency knowledge, self-efficacy, and goal achievement? Do public hospitals in Mexico where providers receive PRONTO training have different maternal and neonatal outcomes than control hospitals? Significance Studies in resource-stable countries have found improved patient outcomes following participation in simulation team training. However, limited-resource countries, like Mexico, rarely have access to such trainings given the high cost of simulation. Acknowledging the potential for low-tech, highly-realistic simulation in resource-limited settings, PRONTO was piloted in 2009. Its impact on patient outcomes has yet to be evaluated. Methods We implemented a matched cluster, quasi-randomized trial of PRONTO training in 24 public hospitals in 3 Mexican states from 2010 to 2012. Intervention hospitals (n = 12) had selected providers (n = 450) participate in PRONTO training. Providers were trained in 2 modules, 2 to 3 months apart focusing on the topics of neonatal resuscitation, obstetric hemorrhage, preeclampsia/eclampsia, shoulder dystocia, teamwork, and communication using obstetric emergency simulations, guided debriefings, skill stations, and team-building exercises. Data collection included baseline facility inventory and chart review, pre-post intervention individual participant testing, and 12 months of follow-up, chart review, and birth observations. Pre-post process indicators were analyzed using linear regression. Outcome data were analyzed using negative binomial regression with a difference-in-difference approach for the 3 months prior to data collection at 4, 8, and 12 months follow-up non-cumulatively. Results Following PRONTO training, knowledge and self-efficacy for physicians and nurses (P<.001-.009) significantly improved for all tested topics. Teamwork scores improved during Module I and were maintained through Module II. Participating hospital teams achieved an average of 6 strategic planning goals per hospital, more than 50% of the goals that they set for themselves during the training. The intervention did not significantly impact rates of hysterectomy, obstetric hemorrhage, preeclampsia, or eclampsia. Impact estimations showed a 44% decrease in hospital-based neonatal mortality rates at 8 months postintervention (incidence rate ratio [IRR], 0.56; 95% confidence interval [CI], 0.13–0.64).There was a significant reduction in the rate of cesareans at 4 months (IRR, 0.83; 95% CI, 0.40–0.29), 8 months (IRR, 0.77; 95% CI, 0.10–0.35), and 12 months (IRR, 0.79; 95% CI, 0.8–0.32) follow-up. Discussion Making simulation accessible globally has the potential to save the lives of mothers and newborns, particularly in the most resource-limited settings. Highly realistic, low-tech simulation coupled with team training can improve provider knowledge, self-efficacy, and teamwork, in addition to neonatal mortality and cesarean rates. More research is needed to assess the program's impact on patient-level measures of morbidity and mortality.