Substance use treatment; Treatment for co-occurring substance use plus either serious mental health illness in adults/serious emotional disturbance in children; Outpatient; Regular outpatient treatment; Naltrexone used in Treatment; Other contracted prescribing entity; No formal relationship with prescribing entity; Does not treat alcohol use disorder; Accepts clients using MAT but prescribed elsewhere; Naltrexone (oral); Medication for mental disorders; Nicotine replacement; Non-nicotine smoking/tobacco cessation; Cognitive behavioral therapy; Motivational interviewing; Relapse prevention; Substance use disorder counseling; Private non-profit organization; State mental health department; Commission on Accreditation of Rehabilitation Facilities (CARF); Medicare; Medicaid; Private health insurance; Cash or self-payment; State-financed health insurance plan other than Medicaid; Sliding fee scale (fee is based on income and other factors); Young adults; Adult women; Pregnant/postpartum women; Adult men; Seniors or older adults; Lesbian, gay, bisexual, transgender, or queer/questioning (LGBTQ); Veterans; Clients with co-occurring mental and substance use disorders; Clients who have experienced sexual abuse; Clients who have experienced trauma; Comprehensive mental health assessment; Comprehensive substance use assessment; Outreach to persons in the community; Screening for tobacco use; Screening for substance use; Screening for mental disorders; Professional interventionist/educational consultant; Drug or alcohol urine screening; 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; Substance use disorder education; Smoking/vaping/tobacco cessation counseling; Individual counseling; Group counseling; Vocational training or educational support (for example, high school coursework, GED preparation, etc.) ; Smoking permitted in designated area; Adults; Seniors; Young adults; Female; Male; Vaping permitted in designated area; Case management service; Mental health services; Social skills development; Transportation assistance; Integrated primary care services