Patient safety is a discipline that emphasizes safety in health care through the prevention, reduction, reporting and analysis of medical error that often leads to adverse effects. The frequency and magnitude of avoidable adverse events experienced by patients was not well known until the 1990s, when multiple countries reported staggering numbers of patients harmed and killed by medical errors. Recognizing that healthcare errors impact 1 in every 10 patients around the world, the World Health Organization calls patient safety an endemic concern. Indeed, patient safety has emerged as a distinct healthcare discipline supported by an immature yet developing scientific framework. There is a significant transdisciplinary body of theoretical and research literature that informs the science of patient safety.