Substance use treatment; Treatment for co-occurring substance use plus either serious mental health illness in adults/serious emotional disturbance in children; Outpatient; Intensive 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; Anger management; Brief intervention; Cognitive behavioral therapy; Contingency management/motivational incentives; Dialectical behavior therapy; Motivational interviewing; Relapse prevention; Substance use disorder counseling; Telemedicine/telehealth therapy; 12-step facilitation; Private non-profit organization; State department of health; The Joint Commission; Federal military insurance (e.g., TRICARE); Private health insurance; Cash or self-payment; Clients with co-occurring mental and substance use disorders; Comprehensive mental health assessment; Comprehensive substance use assessment; Screening for tobacco use; Screening for substance use; Screening for mental disorders; Drug or alcohol urine screening; Aftercare/continuing care; Discharge Planning; Substance use disorder education; Group counseling; Smoking not permitted; Adults; Young adults; Female; Male; Case management service; Mental health services; Social skills development