Information overload has been a phenomenon observed and discussed in the literature since many decades. The research field information logistics addresses the problem of information overload by developing concepts and technologies for improving information flow in organizations. A core subject of demand oriented information supply is how to capture needs and preferences of a user in order to get a fairly complete picture of the demand in question. The paper briefly summarizes the content of a tutorial talk at the RCDL conference and provides a list of relevant literature.