Supported by the Department of Justice’s Bureau of Justice Assistance, the FY22 National Initiatives in Justice and Mental Health Program provided resources to support enhanced law enforcement operations, policies, and responses to people living with mental health and substance use disorders. Led by the Council of State Governments (CSG) Justice Center, this project included establishing a national call center to identify, code, and count calls for service involving people with mental health and substance use disorders to better understand the prevalence of these types of calls and the responses most often dispatched to them.