Dr. Michael Höppner is Deputy Librarian and Head of Library Administration at Bielefeld University Library. He has accompanied the development of online catalogues, document delivery services, and digital libraries including pay-per-view services from technical, service-oriented and administrative points of view and was involved in building up library consortia for electronic journals. Besides the planning and development of library and information services, his main interests are budgeting and cost analysis, personnel employment and development, performance measurement and customer analysis thus bringing together the strategic demand for further user and service orientation and the given fact of restricted resources. As a member of different advisory groups for the Board of Library Directors (AGUB) as well as for the Regional Service Center for Libraries (HBZ) in North Rhine-Westphalia, he is co-author of several working papers. Moreover, he is author of some papers focusing on aspects of digital libraries for mathematics.