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; Short-term residential; No formal relationship with prescribing entity; Does not use medication assisted treatment for alcohol use disorder; Accepts clients using MAT but prescribed elsewhere; 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 for-profit organization; State mental health department; State department of health; The Joint Commission; Private health insurance; Cash or self-payment; Adolescents; 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; Screening for substance use; Screening for mental disorders; Breathalyzer or blood alcohol testing; 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; Recovery coach; Mentoring/peer support; Substance use disorder education; Smoking/vaping/tobacco cessation counseling; Individual counseling; Group counseling; Family counseling; Vocational training or educational support (for example, high school coursework, GED preparation, etc.) ; Smoking not permitted; Adults; Children/adolescents; Young adults; Female; Male; Spanish; Mental health services; Social skills development