ExploreNet is an experimental environment for creating and delivering networked "virtual worlds." This system's style of user interaction was inspired by the concept of a "habitat" as first articulated in the LucasFilm's Habitat system. Players enter and interact in a habitat via their animated alter egos, called "avatars." Habitats may be created for many purposes, including social interaction, entertainment and education. Our focus has been to facilitate the creation of habitats in which virtual communities of learners and mentors interact. This paper presents details of the current ExploreNet system, including its user interface, the means it provides for creating complex behaviors, details of its implementation, the outcomes of several experiments using this system, and our plans for its natural migration to a World Wide Web-based system.