Substance use treatment; Treatment for co-occurring substance use plus either serious mental health illness in adults/serious emotional disturbance in children; Outpatient; Residential/24-hour residential; Regular outpatient treatment; Long-term residential; Does not treat alcohol use disorder; Does not treat opioid use disorders; Medication for mental disorders; Anger management; Motivational interviewing; Matrix Model; Relapse prevention; Substance use disorder counseling; Private non-profit organization; State Substance use treatment agency; State mental health department; State department of health; Federal, or any government funding for substance use treatment programs; Medicaid; Federal military insurance (e.g., TRICARE); Private health insurance; Cash or self-payment; Adolescents; Clients who have experienced trauma; Comprehensive substance use assessment; Interim services for clients; Complete medical history/physical exam; Screening for tobacco use; Screening for substance use; Screening for mental disorders; Drug or alcohol urine screening; HIV testing; STD testing; TB screening; Testing for Hepatitis B (HBV); Testing for Hepatitis C (HCV); Aftercare/continuing care; Discharge Planning; Housing services; Assistance with obtaining social services; Mentoring/peer support; Treatment for other addiction disorder; Substance use disorder education; Smoking/vaping/tobacco cessation counseling; Individual counseling; Group counseling; Family counseling; Smoking not permitted; Adults; Children/adolescents; Young adults; Female; Male; Sign language services for the deaf and hard of hearing; Vaping not permitted; Case management service; Mental health services; Social skills development; Transportation assistance