LE-MH Learning Sites are 10 law enforcement agencies selected by the U.S. Justice Department's Bureau of Justice Assistance (BJA) to serve as resources for law enforcement agencies that want to develop or improve a comprehensive police-mental health collaboration (PMHC) that will improve outcomes for police officers' interactions with people who have mental illness. In 2017, the LE-MH Learning Sites responded to 2,536 requests for technical assistance, conducted 121 site visits, and delivered 236 training programs. In 2016, BJA launched an online toolkit that provides support to law enforcement agencies in planning and implementing programs that improve law enforcement personnel's response to people with mental illness. Profiles in programs and publications related to funding and technical assistance specifically for improving the law enforcement response to mentally ill persons features the federal Justice and Mental Health Collaboration Program (JMHCP), which provides grants and technical assistance for developing and improving police-mental health partnerships in serving mentally ill persons; a national curriculum that expands best practices for police responses to mentally ill persons; and a 42-state survey on mental health and crisis de-escalation training for law enforcement. Checklists are described for how jurisdictional policymakers, law enforcement leaders, and behavioral health agency leaders can assess their agencies and partnerships response to mentally ill persons who are encountered by law enforcement personnel.