This resource, developed to support jail administrators in providing effective treatment for opioid misuse and helping to halt the opioid epidemic in the United States, introduces what has been learned from sheriffs’ and jail administrators’ innovative use of medication-assisted treatment, a cornerstone of best practice for recovery from substance misuse; describes the essential components of these programs; and discusses the latest research on how the programs are best implemented, as well as the medications approved for opioid use disorders.