Mobile crisis response (MCR) systems are designed to provide immediate services to individuals who are experiencing acute behavioral health episodes, including those related to mental illness and substance use. As states grapple with the ongoing health, social, and economic impacts of COVID-19, strategies such as MCR may be a promising intervention to address behavioral health needs in the community. The American Rescue Plan Act created an option for state Medicaid agencies to cover community-based MCR intervention services with an 85 percent federal match for the next five years. This whitepaper highlights the role that state Medicaid agencies play in standing up MCR programs, common implementation challenges, and additional policy considerations as states move toward implementation.