NIJ is seeking proposals for research on sentinel events in the criminal justice system. When bad things happen in a complex system, the cause is rarely a single act, event, or slip-up. More often, bad outcomes like wrongful convictions, mistaken prison releases, and even revictimization are "sentinel events"-defined as significant negative outcomes that signal underlying weaknesses in the system or process. Sentinel events are likely the result of compound errors and, if properly analyzed and addressed, may provide important keys to strengthening the system and preventing future adverse events or outcomes. Even “near misses,” where tragic outcomes are eventually averted, can signal serious underlying weaknesses in the overall system. NIJ is seeking proposals for research that can add to our understanding of how the concept of sentinel events can be used to improve the functioning of justice systems. Funding under this solicitation will support multiple awards for either basic research or for applied studies (including evaluations).