The goal of this paper is to describe the theoretical underpinnings of the construct Para-social Presence and to develop an instrument to measure this construct. Para-social presence refers to the extent to which a medium facilitates a sense of understanding, connection, involvement and interaction among participating social entities. We make a case for treating a web site as a valid social actor and argue that the relationship between a web site and her visitors should be characterized in much the same way one would characterize an inter-personal relationship. We also argue that a web site could possess different levels of para-social presence depending on how it is configured and used. We then develop a research framework that illustrates the impact of new technologies (such as personalization systems) and associated web interface design decisions on perceived communication characteristics of a web site, para-social presence, and subsequent user evaluations of the web site.