Substance use treatment; Outpatient; Outpatient methadone/buprenorphine or naltrexone treatment; Regular outpatient treatment; Methadone used in Treatment; Does not treat alcohol use disorder; Federally-certified Opioid Treatment Program; Methadone maintenance; Methadone maintenance for predetermined time; Methadone; Anger management; Cognitive behavioral therapy; Contingency management/motivational incentives; Relapse prevention; Substance use disorder counseling; Private non-profit organization; State department of health; Commission on Accreditation of Rehabilitation Facilities (CARF); Healthcare Facilities Accreditation Program (HFAP); SAMHSA certification for opioid treatment program (OTP); Drug Enforcement Agency (DEA); Cash or self-payment; Adult women; Pregnant/postpartum women; Clients with co-occurring mental and substance use disorders; Clients who have experienced intimate partner violence, domestic violence; Comprehensive substance use assessment; Outreach to persons in the community; Complete medical history/physical exam; Screening for tobacco use; Screening for substance use; Drug and alcohol oral fluid testing; Drug or alcohol urine screening; STD testing; TB screening; Metabolic syndrome monitoring; Testing for Hepatitis B (HBV); Testing for Hepatitis C (HCV); Discharge Planning; Outcome follow-up after discharge; Housing services; Employment counseling or training; HIV or AIDS education, counseling, or support; Health education services other than HIV/AIDS or hepatitis; Substance use disorder education; Individual counseling; Group counseling; Family counseling; Smoking permitted in designated area; Adults; Young adults; Female; Male; Opioid use disorder clients only; Vaping permitted in designated area; Case management service