This computer based exhibit allows visitors to simulate interactions with potentially HIV+ individuals. They may select the gender and sexual preference of the persons with whom they interact, as well as the characteristics of their behavior, i.e., safe or unsafe sex, IV drug use or not, and if so, whether sterile or unsterilized needles are used. The simulation proceeds by selecting random images of heads until an HIV contact has occurred, based on the relative risk of the interaction. The risk data is based on seroprevalency in San Francisco. Hopefully, the option to select data from around the world will be incorporated to give a global perspective of the epistemology of HIV.