In 1999, the Institute of Medicine (IOM) released its landmark report, To Err Is Human: Building a Safer Health System , which revealed that a significant number of people die annually from medical errors. The report spurred two decades of action on the part of hospitals and health care professionals to improve patient safety. The IOM, renamed the National Academy of Medicine (NAM), is now addressing the issue of clinician well-being. The Action Collaborative on Clinician Well-Being and Resilience (the “action collaborative”) was launched in January 2017 in response to the burgeoning body of evidence that burnout is endemic and affects patient outcomes. The action collaborative has defined “clinician” and “burnout” in Box 1.