A term made famous by a classic human factors study by Cooper of "anesthetic mishaps," though the term had first been coined in the 1950s. Cooper and colleagues brought the technique of critical incident analysis to a wide audience in health care but followed the definition of the originator of the technique. They defined critical incidents as occurrences that are "significant or pivotal, in either a desirable or an undesirable way," though Cooper and colleagues (and most others since) chose to focus on incidents that had potentially undesirable consequences. This concept is best understood in the context of the type of investigation that follows, which is very much in the style of root cause analysis. Thus, significant or pivotal means that there was significant potential for harm (or actual harm), but also that the event has the potential to reveal important hazards in the organization. In many ways, it is the spirit of the expression in quality improvement circles, "every defect is a treasure." In other words, these incidents, whether near misses or disasters in which significant harm occurred, provide valuable opportunities to learn about individual and organizational factors that can be remedied to prevent similar incidents in the future.