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; 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; Cognitive behavioral therapy; Motivational interviewing; Relapse prevention; Substance use disorder counseling; Telemedicine/telehealth therapy; 12-step facilitation; Private for-profit organization; Medicare; Private health insurance; Cash or self-payment; Comprehensive mental health assessment; Comprehensive substance use assessment; Interim services for clients; Screening for substance use; Screening for mental disorders; Aftercare/continuing care; Outcome follow-up after discharge; Substance use disorder education; Smoking/vaping/tobacco cessation counseling; Individual counseling; Marital/couples counseling; Smoking not permitted; Children/adolescents; Female; Male; Vaping not permitted; Mental health services