Disruptive physician behavior is a recognized patient safety problem. Fear of confrontation with a disruptive individual may inhibit speaking up about potential errors and worsen safety culture and teamwork. In this simulation study, neonatal intensive care unit teams were exposed to either rude or neutral comments from an observer during their assigned simulated task. Compared to teams receiving neutral comments, those who were exposed to rudeness performed worse. This study complements prior studies which document perceived consequences of disruptive behavior by demonstrating worse simulated task performance. This work also reveals that rudeness external to a team can affect performance and suggests that a polite work culture would foster patient safety.