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; Medication for mental disorders; Cognitive behavioral therapy; Substance use disorder counseling; Trauma-related counseling; Telemedicine/telehealth therapy; Private non-profit organization; State Substance use treatment agency; State mental health department; State department of health; Council on Accreditation (COA); Federal, or any government funding for substance use treatment programs; Medicare; Medicaid; Federal military insurance (e.g., TRICARE); Private health insurance; Cash or self-payment; State-financed health insurance plan other than Medicaid; Clients with co-occurring mental and substance use disorders; Comprehensive mental health assessment; Comprehensive substance use assessment; Outreach to persons in the community; Screening for tobacco use; Screening for substance use; Screening for mental disorders; Drug or alcohol urine screening; Aftercare/continuing care; Discharge Planning; Outcome follow-up after discharge; Housing services; Assistance with obtaining social services; Mentoring/peer support; Substance use disorder education; Smoking/vaping/tobacco cessation counseling; Individual counseling; Group counseling; Smoking not permitted; Female; Male; Sign language services for the deaf and hard of hearing; Vaping not permitted; Case management service; Mental health services; Social skills development