At present, data from mathematical models, ecologic studies and a clinical trial demonstrate that use of combination antiretroviral therapy (cART) can markedly reduce HIV transmission. Expansion of cART uptake (Treatment as Prevention) is a critical component of biomedical interventions to prevent HIV transmission. Successful implementation is dependent on identifying undiagnosed individuals, linking and retaining them in care and initiating durable and potent cART regimens. This continuum is encapsulated within the framework of the 'Test and Treat', or 'Seek, Test, Treat and Retain' strategies. Currently only 19-28% of all HIV-infected individuals in the USA are estimated to be virologically suppressed. Optimizing the engagement of care cascade represents a critical step to maximize the individual and societal impact of cART and therefore deliver on the promise of HIV Treatment as Prevention.