Substance use treatment; Detoxification; Treatment for co-occurring substance use plus either serious mental health illness in adults/serious emotional disturbance in children; Outpatient; Outpatient detoxification; Outpatient methadone/buprenorphine or naltrexone treatment; Regular outpatient treatment; Methadone used in Treatment; Does not treat alcohol use disorder; Federally-certified Opioid Treatment Program; Methadone maintenance; Methadone; Anger management; Brief intervention; Cognitive behavioral therapy; Motivational interviewing; Matrix Model; Relapse prevention; Substance use disorder counseling; Trauma-related counseling; 12-step facilitation; Private for-profit organization; State Substance use treatment agency; State department of health; Commission on Accreditation of Rehabilitation Facilities (CARF); Private health insurance; Cash or self-payment; Pregnant/postpartum women; Comprehensive substance use assessment; Interim services for clients; Screening for tobacco use; Screening for substance use; Breathalyzer or blood alcohol testing; Drug or alcohol urine screening; STD testing; TB screening; Aftercare/continuing care; Discharge Planning; Outcome follow-up after discharge; Housing services; Assistance with obtaining social services; Mentoring/peer support; Opioids detoxification; Medication routinely used during detoxification; Hepatitis education, counseling, or support; Substance use disorder education; Individual counseling; Group counseling; Family counseling; Smoking not permitted; Adults; Young adults; Female; Male; Spanish; Case management service; Early intervention for HIV; Social skills development