BACKGROUND:Teamwork is essential to safety. Few studies focus on teamwork between nurses and physicians in emergency departments (EDs). OBJECTIVE:The aim of this study was to examine differences between staff in the interventional group EDs (IGEDs) and control group EDs (CGEDs) on perception of job environment, autonomy, and control over practice. METHODOLOGY:This was a comparative cross-sectional study of the impact of teamwork on perceptions of job environment, autonomy, and control over practice by registered nurses and physicians (MDs) in EDs. RESULTS:Staff in the IGEDs showed significant differences compared with staff who worked in the CGEDs on staff perception of job environment, autonomy, and control over practice. CONCLUSION:Active teamwork practice was associated with increased perceptions of a positive job environment, autonomy, and control over practice of both nurses and physicians.