In the mid-1980s, the anesthesia departments at hospitals affiliated with Harvard Medical School were faced with a challenge: mounting medical malpractice costs. Malpractice insurance was provided by the Controlled Risk Insurance Company (CRICO), a patient safety and medical malpractice insurance company owned by and providing service to the Harvard medical community. CRICO spearheaded an effort to reduce these costs and ultimately found a way to decrease the risks associated with anesthesia. Here, we chronicle events that led to the dramatic changes in medical practice that resulted from the activities of a small group of concerned anesthesiologists at Harvard-affiliated hospitals. We place these events in a historical perspective and explore how other specialties followed this example, and end with current strategies that minimize the risk associated with anesthesia. We conducted interviews with principals who formulated original standards of patient monitoring. In addition, we consulted documents in the public domain and primary source material. Efforts of these pioneers resulted in the establishment of the seminal Harvard-based anesthesia monitoring standards for minimal monitoring. What followed was an unprecedented transformation of the entire field. After the implementation of these standards at Harvard-affiliated hospitals, the American Society of Anesthesiologists (ASA) adopted "Standards for Basic Anesthetic Monitoring" for use during the administration of all anesthetics in the United States. Other nations have since adopted similar guidelines and these practices have resulted in significant improvements in patient safety. Currently, we estimate mortality due to anesthesia in healthy patients to be 1:400,000-perhaps as much as 10 times lower since the early 1980s. What began as an attempt to lower medical malpractice costs in a group of university hospitals became a worldwide effort that resulted in improvements in patient safety. Other specialties have adopted similar measures. Currently, an attitude and appreciation of safety are exemplified by several practices that include among others-the adherence to these patient safety guidelines, simulator training, the promulgation of standards and guidelines by ASA, and the use of a safety checklist before induction of anesthesia.