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; Methadone used in Treatment; Buprenorphine used in Treatment; Naltrexone used in Treatment; Does not treat alcohol use disorder; Buprenorphine maintenance; Federally-certified Opioid Treatment Program; Methadone maintenance; Prescribes naltrexone; Methadone; Buprenorphine with naloxone; Naltrexone (oral); Medication for mental disorders; Substance use disorder counseling; Private non-profit organization; State department of health; Commission on Accreditation of Rehabilitation Facilities (CARF); Medicaid; Cash or self-payment; Adult women; Adult men; 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 tobacco use; Screening for substance use; Screening for mental disorders; Drug and alcohol oral fluid testing; Drug or alcohol urine screening; HIV testing; STD testing; TB screening; Metabolic syndrome monitoring; Testing for Hepatitis B (HBV); Testing for Hepatitis C (HCV); Aftercare/continuing care; Discharge Planning; Naloxone and overdose education; Outcome follow-up after discharge; Self-help groups; Housing services; Assistance with obtaining social services; Mentoring/peer support; Treatment for gambling disorder; HIV or AIDS education, counseling, or support; Hepatitis education, counseling, or support; Health education services other than HIV/AIDS or hepatitis; Substance use disorder education; Individual counseling; Group counseling; Family counseling; Marital/couples counseling; Smoking permitted in designated area; Adults; Young adults; Female; Male; Opioid use disorder clients only; Other languages (excluding Spanish); Arabic; German; Hebrew; Vietnamese; Vaping permitted in designated area; Case management service; Early intervention for HIV; Mental health services; Social skills development; Transportation assistance; Integrated primary care services; Suicide prevention services