Substance use and HIV have become entwined epidemics that have an impact on individual’s physical and mental health outcomes. Of the 1.2 million people living with HIV in the US, 77.0% are currently linked to HIV care and 51.0% are retained in HIV care. However, fewer than fifty percent are currently being prescribed HAART to treat their HIV infection (CDC, 2011). An HIV Care Continuum model has been developed and adopted by the CDC as a sequential step-by-step process that helps guide individuals living with HIV achieve viral load suppression (Kilmarx & Mutasa-Apollo, 2013). The goal of this paper is to examine if there are differences within the HIV Care Continuum model for individuals seeking opioid substitution therapy treatment (OST) vs. non-OST treatment seeking participants.