 The HIV epidemic is a major global health challenge. People in developing nations have limited access to life-sustaining antiretrovirals and account for over 95 of the 5 million new HIV infections annually. The development of a safe, effective, and widely accessible HIV vaccine is paramount in these areas. The adenoviral vector vaccine VRC-HIVADV014-00-VP has been shown to elicit a CD8 cytotoxic lymphocyte CTL response believed to be crucial in an effective preventive HIV vaccine. The purpose of this study is to determine the safety and immunogenicity of VRC-HIVADV014-00-VP in HIV uninfected adults. In this study, HIV uninfected individuals with low levels of pre-existing adenovirus neutralizing antibodies will receive different doses of the preventive vaccine to determine its safety, tolerability, and immunogenicity. 