An emergency psychiatry-mobile crisis program was established in 1987 in Charleston, South Carolina, linking professionals from the mental health center, the university, and the local police department. The program has two goals: to provide emergency psychiatric services to persons in the community and to train psychiatric residents in crisis intervention. Mental health staff act as consultants to the police in some situations, and in others the police provide security. The authors describe the development of the collaboration with police and important features of the program. Three cases illustrate how such collaboration can be of mutual benefit and can save lives.