Enter the text here that is the new abstract information for your application. This section must be no longer than 30 lines of text. Effective treatment for OUD has been shown to improve patient outcomes, and reduce healthcare costs; however, evidence of this effect in primary care settings is severely limited. The health economic findings from this study will supplement the parent PROUD trial’s results regarding clinical effectiveness and implementation outcomes and provide critical contextual information for health systems and other healthcare stakeholders. The study will evaluate the economic viability of the PROUD collaborative care model for OUD; that is, from the perspective of the healthcare sector, to what extent do the downstream cost savings associated with improved patient outcomes offset the additional costs of the PROUD intervention. The specific aims are to: 1) estimate the start-up and ongoing management costs of the PROUD intervention; 2) assess costs associated with healthcare utilization for patients who receive primary care treatment in PROUD and usual care clinics, and have been identified with recognized OUDs prior to clinic randomization; 3) estimate the economic value of the PROUD intervention, measured as net monetary benefit (NMB, incremental benefit – incremental cost), from the healthcare sector perspective. This study is part of the NIH’s Helping to End Addiction Long-term (HEAL) initiative to speed scientific solutions to the national opioid public health crisis. The NIH HEAL Initiative bolsters research across NIH to improve treatment for opioid misuse and addiction.