Substance use treatment; Treatment for co-occurring substance use plus either serious mental health illness in adults/serious emotional disturbance in children; Outpatient; Residential/24-hour residential; Outpatient day treatment or partial hospitalization; Intensive outpatient treatment; Regular outpatient treatment; Long-term residential; Naltrexone used in Treatment; No formal relationship with prescribing entity; Accepts clients using medication assisted treatment for alcohol use disorder but prescribed elsewhere; No formal relationship with prescribing entity; Accepts clients using MAT but prescribed elsewhere; Naltrexone (oral); Naltrexone (extended-release, injectable); Lofexidine; Clonidine; Medication for mental disorders; Nicotine replacement; Non-nicotine smoking/tobacco cessation; Brief intervention; Cognitive behavioral therapy; Contingency management/motivational incentives; Community reinforcement plus vouchers; Motivational interviewing; Relapse prevention; Substance use disorder counseling; Trauma-related counseling; 12-step facilitation; Private for-profit organization; State Substance use treatment agency; State mental health department; The Joint Commission; Medicaid; Cash or self-payment; Young adults; Adult women; Adult men; Clients with co-occurring mental and substance use disorders; Clients with co-occurring pain and substance use disorders; 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; 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; Self-help groups; Housing services; Assistance with obtaining social services; Recovery coach; Mentoring/peer support; Employment counseling or training; Substance use disorder education; Smoking/vaping/tobacco cessation counseling; Individual counseling; Group counseling; Family counseling; Smoking permitted in designated area; Adults; Young adults; Female; Male; Vaping permitted in designated area; Case management service; Mental health services; Social skills development; Transportation assistance; Suicide prevention services