Among recommendations to address medical errors, the Institute of Medicine (IOM) called for the creation of a nationwide mandatory reporting system for adverse events that result in death or serious injury, implemented through state collection of standardized data. This briefing reviews the system in Maine. Health care facilities are required to report sentinel events to the state Department of Human Services Division of Licensure and Certification. The Division reviews the events and takes appropriate action. Reports are confidential and privileged, and reporters are immune from liability for reporting events. The Division will develop an annual report of summary data. Facilities that knowingly violate the act are subject to fine. Funding for two positions and information system development was provided.