BACKGROUND: Simulation offers an opportunity to practice neonatal resuscitation and test clinical systems to improve safety. The authors used simulation-based clinical systems testing (SbCST) with a Healthcare Failure Mode and Effect Analysis (HFMEA) rubric to categorize and quantify latent safety threats (LSTs) during in situ training in eight rural delivery hospitals. The research team hypothesized that most LSTs would be common across hospitals. LST themes were identified across sites. METHODS: Between May 2019 and May 2023, the neonatal simulation team conducted half-day training sessions including a total of 177 interprofessional delivery room team members. Teams participated in skills stations, followed by in situ simulations with facilitated debriefs. Facilitators included neonatologists and simulation faculty trained in HFMEA. HFMEA rubrics were completed for each site with mitigation strategies captured on follow-up. LSTs were compared across sites. RESULTS: A total of 67 distinct LSTs were identified. Forty-one of 67 (61.2%) were shared by more than one hospital, and 26 (38.8%) were unique to individual hospitals. LSTs were distributed across five systems categories and three teams categories. The 4 LSTs detected at 75% or more of hospitals were lack of clear newborn blood transfusion protocols, inconsistent use of closed-loop communication, inconsistent processes for accessing additional resources, and inconsistent use of a recorder. CONCLUSION: Use of SbCST across a health system allows for comparison of LSTs at each site and identification of common opportunities to mitigate safety threats. Systemwide analysis provides leaders with data needed to guide resource allocation to track and ensure effective implementation of solutions for prioritized LSTs. Identification of themes may allow other hospitals that have not participated in simulation testing to engage in prospective readiness efforts.