Substance use treatment; Treatment for co-occurring substance use plus either serious mental health illness in adults/serious emotional disturbance in children; Outpatient; Outpatient methadone/buprenorphine or naltrexone treatment; Regular outpatient treatment; Methadone used in Treatment; Buprenorphine used in Treatment; Does not treat alcohol use disorder; Buprenorphine maintenance; Buprenorphine maintenance for predetermined time; Federally-certified Opioid Treatment Program; Methadone maintenance; Methadone maintenance for predetermined time; Methadone; Buprenorphine with naloxone; Clonidine; Anger management; Cognitive behavioral therapy; Contingency management/motivational incentives; Dialectical behavior therapy; Motivational interviewing; Relapse prevention; Substance use disorder counseling; Telemedicine/telehealth therapy; Trauma-related counseling; Private non-profit organization; State Substance use treatment agency; Commission on Accreditation of Rehabilitation Facilities (CARF); Council on Accreditation (COA); Federal, or any government funding for substance use treatment programs; Medicare; Medicaid; Private health insurance; Cash or self-payment; State-financed health insurance plan other than Medicaid; Adult women; Pregnant/postpartum women; Adult men; Seniors or older adults; Lesbian, gay, bisexual, transgender, or queer/questioning (LGBTQ); Veterans; Criminal justice (other than DUI/DWI)/Forensic clients; Clients with co-occurring mental 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 tobacco use; Screening for substance use; Screening for mental disorders; Breathalyzer or blood alcohol testing; Drug and alcohol oral fluid testing; Drug or alcohol urine screening; STD testing; TB screening; Metabolic syndrome monitoring; Aftercare/continuing care; Discharge Planning; Naloxone and overdose education; Assistance with obtaining social services; Mentoring/peer support; HIV or AIDS education, counseling, or support; Substance use disorder education; Individual counseling; Group counseling; Family counseling; Smoking not permitted; Adults; Seniors; Young adults; Female; Male; Spanish; Mental health services