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; Does not treat alcohol use disorder; Does not treat opioid use disorders; Private for-profit organization; Cash or self-payment; Young adults; Adult women; Adult men; Veterans; Members of military families; Criminal justice (other than DUI/DWI)/Forensic clients; Clients with co-occurring mental and substance use disorders; Clients who have experienced sexual abuse; Clients who have experienced intimate partner violence, domestic violence; Clients who have experienced trauma; Comprehensive mental health assessment; Comprehensive substance use assessment; Screening for substance use; Screening for mental disorders; Individual counseling; Group counseling; Smoking permitted in designated area; Adults; Young adults; Female; Male; Vaping permitted in designated area; Mental health services