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; Methadone used in Treatment; Buprenorphine used in Treatment; Naltrexone used in Treatment; Does not treat alcohol use disorder; Buprenorphine maintenance; Buprenorphine maintenance for predetermined time; Federally-certified Opioid Treatment Program; Methadone maintenance; Methadone maintenance for predetermined time; Prescribes buprenorphine; Prescribes naltrexone; Relapse prevention with naltrexone; Methadone; Buprenorphine with naloxone; Buprenorphine without naloxone; Naltrexone (extended-release, injectable); Anger management; Brief intervention; Cognitive behavioral therapy; Dialectical behavior therapy; Motivational interviewing; Relapse prevention; Substance use disorder counseling; Trauma-related counseling; 12-step facilitation; Private non-profit organization; State Substance use treatment agency; State department of health; Commission on Accreditation of Rehabilitation Facilities (CARF); Federal, or any government funding for substance use treatment programs; Medicare; Medicaid; Cash or self-payment; Pregnant/postpartum women; Clients with co-occurring mental and substance use disorders; 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; Breathalyzer or blood alcohol testing; Drug and alcohol oral fluid testing; Drug or alcohol urine screening; TB screening; Aftercare/continuing care; Discharge Planning; Naloxone and overdose education; Outcome follow-up after discharge; Housing services; Assistance with obtaining social services; Recovery coach; Mentoring/peer support; Employment counseling or training; 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; Smoking/vaping/tobacco cessation counseling; Individual counseling; Group counseling; Family counseling; Marital/couples counseling; Vocational training or educational support (for example, high school coursework, GED preparation, etc.) ; Smoking not permitted; Adults; Young adults; Female; Male; Case management service; Early intervention for HIV; Mental health services; Social skills development; Transportation assistance