The use of human mucosal tissue models is an important tool advancing our understanding of the specific mechanisms of sexual HIV transmission. Despite 30 years of study, major gaps remain, including how HIV-1 transverses the epithelium and the identity of the early immune targets (gate keepers). Because defining HIV-1 transmission in vivo is difficult, mucosal tissue is being used ex vivo to identify key steps in HIV-1 entry and early dissemination. Elucidating early events of HIV-1 infection will help us develop more potent and specific HIV-1 preventatives such as microbicides and vaccines. Mucosal tissue has been incorporated into testing regimens for antiretroviral drugs and monoclonal antibodies. The use of mucosal tissue recapitulates the epithelium and immune cells that would be exposed in vivo to virus and drug. This review will discuss the use of mucosal tissue to better understand HIV-1 pathogenesis and prevention modalities.