Substance use treatment; Treatment for co-occurring substance use plus either serious mental health illness in adults/serious emotional disturbance in children; Outpatient; Outpatient methadone/buprenorphine or naltrexone treatment; Regular outpatient treatment; Naltrexone used in Treatment; Does not treat alcohol use disorder; Prescribes naltrexone; Relapse prevention with naltrexone; Naltrexone (oral); Clonidine; Medication for mental disorders; Anger management; Brief intervention; Cognitive behavioral therapy; Motivational interviewing; Relapse prevention; Substance use disorder counseling; Trauma-related counseling; Telemedicine/telehealth therapy; Local, county, or community government; State mental health department; Medicare; Medicaid; Federal military insurance (e.g., TRICARE); Private health insurance; Cash or self-payment; Adolescents; Young adults; Adult women; Pregnant/postpartum women; Adult men; Seniors or older adults; Lesbian, gay, bisexual, transgender, or queer/questioning (LGBTQ); Veterans; Active duty military; Members of military families; Criminal justice (other than DUI/DWI)/Forensic clients; Clients with co-occurring mental and substance use disorders; Clients with co-occurring pain and substance use disorders; Clients with HIV or AIDS; Clients who have experienced sexual abuse; Clients who have experienced intimate partner violence, domestic violence; Clients who have experienced trauma; Comprehensive mental health assessment; Comprehensive substance use assessment; Screening for substance use; Screening for mental disorders; Aftercare/continuing care; Discharge Planning; Assistance with obtaining social services; Treatment for gambling disorder; Treatment for other addiction disorder; Medication routinely used during detoxification; Substance use disorder education; Smoking/vaping/tobacco cessation counseling; Individual counseling; Group counseling; Family counseling; Marital/couples counseling; Smoking not permitted; Seniors; Female; Male; Vaping not permitted; Case management service; Domestic violence services, including family or partner; Mental health services; Social skills development; Transportation assistance; Integrated primary care services; Suicide prevention services