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; No formal relationship with prescribing entity; Accepts clients using medication assisted treatment for alcohol use disorder but prescribed elsewhere; No formal relationship with prescribing entity; Accepts clients using MAT but prescribed elsewhere; Cognitive behavioral therapy; Trauma-related counseling; Telemedicine/telehealth therapy; Private for-profit organization; State department of health; Federal military insurance (e.g., TRICARE); Private health insurance; Cash or self-payment; Sliding fee scale (fee is based on income and other factors); Adolescents; Young adults; Adult women; Pregnant/postpartum women; Adult men; Seniors or older adults; Lesbian, gay, bisexual, transgender, or queer/questioning (LGBTQ); Veterans; Active duty military; Members of military families; Clients with co-occurring mental and substance use disorders; Clients with co-occurring pain and substance use disorders; Clients with HIV or AIDS; Clients who have experienced sexual abuse; Clients who have experienced intimate partner violence, domestic violence; Clients who have experienced trauma; Comprehensive substance use assessment; Screening for substance use; Screening for mental disorders; Aftercare/continuing care; Outcome follow-up after discharge; Treatment for other addiction disorder; Substance use disorder education; Individual counseling; Family counseling; Marital/couples counseling; Smoking not permitted; Children/adolescents; Seniors; Female; Male; Vaping not permitted; Mental health services