Dr. Joseph Muller is a senior physician advisor in the Substance Abuse and Mental Health Services Administration’s Center for Substance Abuse Treatment. Before joining SAMHSA, he worked as a primary care physician and medical director for addiction treatment at a community health center in Washington, DC. He was also the medical director of the opioid treatment program at the DC Department of Corrections. Dr. Muller held the 2019–2020 addiction medicine fellowship from Johns Hopkins University.