He conducts implementation science research on HIV antiretroviral therapy (ART) delivery in resource limited settings, working within collaborations between UCSF and collaborators in Uganda and Kenya. The goal of this research is to develop, test and understand the most optimal ways in which earlier ART can be delivered to affected populations in Sub Saharan Africa. He is also conducting clinical translational research on the immunologic and virologic impact of early versus deferred initiation of HIV antiretroviral therapy. The goal of this research is to better define the optimal time for ART initiation, and to explore and understand the biology of early HIV infection and what impact early-initiated ART exerts on it.