Substance use treatment; Treatment for co-occurring substance use plus either serious mental health illness in adults/serious emotional disturbance in children; Outpatient; Regular outpatient treatment; Does not use MAT for opioid use disorders; Medication for mental disorders; Local, county, or community government; State Substance use treatment agency; State mental health department; Medicare; Medicaid; Private health insurance; Cash or self-payment; State-financed health insurance plan other than Medicaid; Sliding fee scale (fee is based on income and other factors); Comprehensive mental health assessment; Screening for substance use; Screening for mental disorders; Aftercare/continuing care; Discharge Planning; Outcome follow-up after discharge; Assistance with obtaining social services; Mentoring/peer support; Treatment for other addiction disorder; Substance use disorder education; Individual counseling; Family counseling; Marital/couples counseling; Smoking permitted without restriction; Female; Male; Specially designed program for DUI/DWI clients; Case management service; Domestic violence services, including family or partner; Mental health services