Collaborative Care for Polysubstance Use in Primary Care Settings (Co-Care)

PCP Inclusion Criteria: * Licensed medical professional (MD, DO, NP, PA) who is able to prescribe controlled substances (Schedule III), or medical trainee meeting the requirements below. * Serves as a primary care provider to adult patients (18 years of age and over) of the study clinic(s) during direct patient care sessions. * Willing to be randomized to either of the study conditions. a. Medical trainees (physicians who are residents or fellows), are eligible if they have at least one continuity clinic session per week on average in the study clinic. Trainees must have plans to be working in a study clinic for approximately 8 months or longer. They must be able to provide prescriptions for controlled substances (Schedule III) either directly or through their preceptor(s). Patient Inclusion Criteria: * The participant's PCP is enrolled in the study. * Age 18 years or older. * Spoken and written proficiency in language of study materials, as determined by patient self-report and research staff evaluation. * Moderate to severe substance use disorder for opioids, stimulants, and/or alcohol, (defined as meeting four or more DSM-5 criteria per substance as measured on the CIDI-adapted for DSM-5). * a) Patients having alcohol use disorder without an opioid or stimulant SUD are required to have current opioid or stimulant use, as measured on the TAPS tool or baseline monthly survey. * Current polysubstance use, defined as self-reported use of two or more substances of concern in…