Approximately 1,000 people in the United States were fatally shot by police officers during 2018, and people with mental illness were involved in approximately 25 percent of those fatalities. Crisis Intervention Team (CIT) training is a specialized police curriculum that aims to reduce the risk of serious injury or death during an emergency interaction between persons with mental illness and police officers. CIT has been implemented widely both nationally and internationally. Given the increasing resources devoted to CIT, efforts to analyze its effectiveness and outcomes relative to other approaches are important. Studies of CIT and similar interventions are found within both the mental health and the criminal justice arenas, which use very different terminologies, approaches, and outcome studies, rendering unified analyses challenging. This article describes the CIT model and reviews several recent systematic analyses of studies concerning the effects of CIT. Studies generally support that CIT has beneficial officer-level outcomes, such as officer satisfaction and self-perception of a reduction in use of force. CIT also likely leads to prebooking diversion from jails to psychiatric facilities. There is little evidence in the peer-reviewed literature, however, that shows CIT’s benefits on objective measures of arrests, officer injury, citizen injury, or use of force.