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 use medication assisted treatment for alcohol use disorder; Does not treat opioid use disorders; Private for-profit organization; State Substance use treatment agency; State mental health department; Medicare; Medicaid; Federal military insurance (e.g., TRICARE); Private health insurance; Cash or self-payment; State-financed health insurance plan other than Medicaid; Comprehensive mental health assessment; Comprehensive substance use assessment; Screening for tobacco use; Screening for substance use; Screening for mental disorders; Drug and alcohol oral fluid testing; Drug or alcohol urine screening; Aftercare/continuing care; Discharge Planning; Outcome follow-up after discharge; Assistance with obtaining social services; Treatment for other addiction disorder; Substance use disorder education; Individual counseling; Family counseling; Marital/couples counseling; Smoking permitted in designated area; Children/adolescents; Female; Male; Specially designed program for DUI/DWI clients; Vaping permitted in designated area; Domestic violence services, including family or partner; Mental health services; Social skills development