The document discusses collaborative information retrieval (CIR). It defines CIR as involving groups searching for information together to address a shared task or information need. The document outlines key aspects of collaboration, including tasks like travel planning and bibliographic search. It also discusses how CIR differs from personalized IR, collaborative filtering, and social IR in aspects like the user, personalization, collaboration nature, and information goals. CIR aims to support groups jointly searching for, discussing, and synthesizing information through both synchronous and asynchronous collaboration and communication.