s: problems classified from the user perspective 515 Journal of Information Science, 31 (6) 2005, pp. 515–526 © CILIP, DOI: 10.1177/0165551505057014 Michela Montesi University of Amsterdam, Amsterdam, The Netherlands Blanca Gil Urdiciain Universidad Complutense de Madrid, Spain Received 3 March 2005 Revised 20 April 2005