Abstract: An interactive collaborative information visualization system provides improved visualizations of relationships or connections in collaborative information relating to network interaction media such as email and email lists, conferencing systems and bulletin boards, chats, multi-user dungeons (MUDs), multi-user games and graphical virtual worlds, etc. In one implementation, network graphs in various display or visualization formats represent the collaborative information as nodes that are connected together by links. With reference to collaborative information about Usenet newsgroups, one visualization format provides an inter-group visualization in which newsgroup nodes are linked together by links representing messages that are cross-posted between the newsgroups. Other visualization format can be provided. In one implementation, a graphical user interface allows a user to control the database filter to select the selected portion of the collaborative information to be obtained and measured.