Substance use treatment; Treatment for co-occurring substance use plus either serious mental health illness in adults/serious emotional disturbance in children; Outpatient; Intensive outpatient treatment; Regular outpatient treatment; In-network prescribing entity; No formal relationship with prescribing entity; Accepts clients using medication assisted treatment for alcohol use disorder but prescribed elsewhere; In-network prescribing entity; No formal relationship with prescribing entity; Accepts clients using MAT but prescribed elsewhere; Brief intervention; Motivational interviewing; Matrix Model; Relapse prevention; Substance use disorder counseling; Telemedicine/telehealth therapy; Trauma-related counseling; 12-step facilitation; Private non-profit organization; State mental health department; State department of health; Federally Qualified Health Center; Federal, or any government funding for substance use treatment programs; IHS/Tribal/Urban (ITU) funds; Medicaid; 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; Screening for substance use; Screening for mental disorders; Professional interventionist/educational consultant; Breathalyzer or blood alcohol testing; Drug and alcohol oral fluid testing; Drug or alcohol urine screening; Aftercare/continuing care; Discharge Planning; Naloxone and overdose education; Substance use disorder education; Individual counseling; Smoking permitted in designated area; Children/adolescents; Female; Male; Specially designed program for DUI/DWI clients; Vaping permitted in designated area; Mental health services