Patient safety incidents occurring in prehospital care settings are gaining increasing attention. This systematic review including both peer-reviewed studies and grey literature found that the incidence rate of prehospital patient safety incidents is similar to hospital rates. The authors identified an average of 5.9 patient safety incidents per 100 records/transports/patients occurring in prehospital care; approximately 15% of these incidents resulted in patient harm. The authors discuss methodological challenges to preshopital care research and make recommendations for future studies.