A new study by Jeanne C. Marsh (CHAS Director and George Herbert Jones Distinguished Service Professor at the Crown Family School of Social Work, Policy, and Practice) aims to identify the relative strengths of association of medication and health and social services in comprehensive substance use disorder (SUD) treatment. The researchers use a novel variance decomposition method to assess the relative strength of association of six active ingredients in SUD treatment, including methadone medication, access services, SUD counseling, matched service ratio, client-provider relationship, and treatment duration. Results from the study showed that methadone accounted for the greatest relative strength of association at 35.4%, compared with 23.8% for treatment duration, 15.4% for client-provider relationship, and 11.2% for matched service ratio. Access and SUD counseling accounted for modest strengths of association. The findings indicate somewhat greater strength of association of methadone compared with other services and service strategies overall. Furthermore, they reinforce the importance of both medication and services and service strategies in the design and development of effective models of service delivery.