This presentation outlines the principles of information seeking as a dialogue and walk though concrete examples that illustrate the principles of human-computer information retrieval (HCIR). The foundation is an interactive set retrieval approach that responds to queries with an overview of the user\'s current context and an organized set of options for incremental exploration. Contextual summaries of document sets optimize the system\'s communication with the user, while query refinement options optimize user\'s communication with the system. By enabling bidirectional communication between the user and the system, we can address the inherent limitations of best-match approaches.