div style="padding-bottom:10px;" class="first" id="id1">Even before the partial success of a preventive HIV vaccine in a recent Phase III clinical trial, there has been an active discovery effort to determine one or more immune correlates of protection in HIV infection. This effort has been hampered by the lack of natural protective immunity against HIV. I will discuss lessons learned from the STEP and RV144 trials and how the Vaccine Research Center is proceeding with the HVTN505 study. I will discuss efforts to elicit broadly neutralizing antibodies and the importance of establishing correlates of immunity from studies in humans.