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; Private for-profit organization; State department of health; Cash or self-payment; Adolescents; Young adults; Adult women; Adult men; Clients with co-occurring mental and substance use disorders; Comprehensive substance use assessment; Interim services for clients; Screening for substance use; Screening for mental disorders; Professional interventionist/educational consultant; Breathalyzer or blood alcohol testing; Drug or alcohol urine screening; Aftercare/continuing care; Discharge Planning; Naloxone and overdose education; Mentoring/peer support; Substance use disorder education; Group counseling; Family counseling; Marital/couples counseling; Smoking permitted in designated area; Female; Male