Introduction Poor communication among obstetric and pediatric professionals is associated with adverse perinatal events leading to severe disability and neonatal mortality. This study evaluated the effectiveness of an interdisciplinary simulation-based training (SBT) program to improve delivery room communication between obstetric and pediatric teams. Methods Obstetric and pediatric teams participated in an SBT annually during 3 academic years, 2008–2011 (Y1–Y3), in a prospective, observational study. Eligible participants (n = 228) included attendings, fellows, house staff, midlevel providers, and nurses involved in delivery room care. Simulations were videotaped and evaluated using a validated 20-item checklist of best communication practices. Checklist scores were compared across years with the Kruskal-Wallis test. Providers were also surveyed annually regarding communication during actual deliveries using a standardized questionnaire. Ratings were analyzed using two-way analysis of covariance. Results At least 60% of eligible providers participated in 1 or more SBT sessions and completed surveys annually. Checklist scores on communication during SBT improved from Y1 (median, 6; interquartile range, 4) to Y3 (median, 11; interquartile range, 6) (P < 0.001). Survey results showed the perception of improvement over time in interteam communication during actual deliveries by obstetric (P < 0.005) and pediatric (P < 0.0001) providers. The obstetric team also perceived improved provider communication with the family (P < 0.05). Conclusions Communication during SBT as well as the perception of communication during actual deliveries improved across the study period. The potential of a checklist to standardize delivery room communication and improve patient outcomes merits further investigation.