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 treat alcohol use disorder; Does not treat opioid use disorders; Medication for mental disorders; Cognitive behavioral therapy; Motivational interviewing; Telemedicine/telehealth therapy; Private for-profit organization; State Substance use treatment agency; State mental health department; State department of health; Commission on Accreditation of Rehabilitation Facilities (CARF); Medicaid; Cash or self-payment; State-financed health insurance plan other than Medicaid; Adolescents; Criminal justice (other than DUI/DWI)/Forensic clients; Clients with co-occurring mental and substance use disorders; Clients who have experienced intimate partner violence, domestic violence; Clients who have experienced trauma; Comprehensive mental health assessment; Comprehensive substance use assessment; Interim services for clients; Outreach to persons in the community; Screening for substance use; Screening for mental disorders; Drug or alcohol urine screening; Aftercare/continuing care; Discharge Planning; Outcome follow-up after discharge; Housing services; Assistance with obtaining social services; Substance use disorder education; Individual counseling; Family counseling; Smoking not permitted; Adults; Children/adolescents; Young adults; Female; Male; Vaping not permitted; Case management service; Mental health services; Social skills development; Transportation assistance; Suicide prevention services