Substance use treatment; Treatment for co-occurring substance use plus either serious mental health illness in adults/serious emotional disturbance in children; Outpatient; Outpatient day treatment or partial hospitalization; Outpatient methadone/buprenorphine or naltrexone treatment; Regular outpatient treatment; Buprenorphine used in Treatment; Does not treat alcohol use disorder; Buprenorphine maintenance; Buprenorphine maintenance for predetermined time; Prescribes buprenorphine; Buprenorphine with naloxone; Buprenorphine without naloxone; Clonidine; Medication for mental disorders; Substance use disorder counseling; Telemedicine/telehealth therapy; Private for-profit organization; State Substance use treatment agency; State mental health department; State department of health; Council on Accreditation (COA); SAMHSA certification for opioid treatment program (OTP); Drug Enforcement Agency (DEA); Medicaid; Private health insurance; Cash or self-payment; State-financed health insurance plan other than Medicaid; Adolescents; Young adults; Adult women; Pregnant/postpartum women; Adult men; Seniors or older adults; Lesbian, gay, bisexual, transgender, or queer/questioning (LGBTQ); Members of military families; Criminal justice (other than DUI/DWI)/Forensic clients; Clients with co-occurring mental 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; Complete medical history/physical exam; Screening for tobacco use; Screening for substance use; Screening for mental disorders; Drug and alcohol oral fluid testing; Drug or alcohol urine screening; Aftercare/continuing care; Discharge Planning; Naloxone and overdose education; Outcome follow-up after discharge; Housing services; Assistance with obtaining social services; Mentoring/peer support; Employment counseling or training; Health education services other than HIV/AIDS or hepatitis; Substance use disorder education; Smoking/vaping/tobacco cessation counseling; Individual counseling; Group counseling; Family counseling; Marital/couples counseling; Smoking permitted without restriction; Seniors; Female; Male; Spanish; Sign language services for the deaf and hard of hearing; Vaping permitted without restriction; Case management service; Mental health services; Social skills development; Suicide prevention services