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; Other contracted prescribing entity; Accepts clients using medication assisted treatment for alcohol use disorder but prescribed elsewhere; Other contracted prescribing entity; Accepts clients using MAT but prescribed elsewhere; Cognitive behavioral therapy; Motivational interviewing; Relapse prevention; Substance use disorder counseling; Telemedicine/telehealth therapy; Private non-profit organization; State Substance use treatment agency; State mental health department; Federal, or any government funding for substance use treatment programs; Medicaid; Adolescents; Clients with co-occurring mental and substance use disorders; Comprehensive mental health assessment; Comprehensive substance use assessment; Interim services for clients; Outreach to persons in the community; Screening for substance use; Screening for mental disorders; Drug or alcohol urine screening; Aftercare/continuing care; Discharge Planning; Self-help groups; Housing services; Assistance with obtaining social services; Mentoring/peer support; Substance use disorder education; Individual counseling; Group counseling; Smoking permitted in designated area; Children/adolescents; Female; Male; Sign language services for the deaf and hard of hearing; Spanish; Vaping permitted in designated area; Case management service; Mental health services; Social skills development; Transportation assistance; Integrated primary care services