Background: South Africa has a generalised HIV epidemic which is managed through free Antiretroviral Therapy (ART). Adherence to ART has emerged as a crucial issue in HIV/AIDS therapeutics. Purpose: The aim of the study was to explore determining factors for poor and excellent adherence to ART for HIV positive patients residing in Barberton, a mining town in Mpumalanga Province. Methodology: A generic qualitative research design was undertaken. Data was collected through in-depth qualitative interviews from a purposive sample of 13 ART patients. Qualitative interpretive analysis was employed. Findings: The study found that excellent adherence to ART is significantly associated with the availability, effectiveness and comprehensiveness of HIV services, psychological support and medical advances. Side effects of ART, opportunistic infections and alcohol and drug use hinder adherence. However, longer duration on ART enhanced self-efficacy and facilitated adherence. Successful ART is dependent on taking ARVs as prescribed and executing necessary lifestyle changes. / Health Studies / M.P.H.