Adoracion de Miguel is Professor at Polytechnic School (Universidad Carlos III de Madrid). She received her M.S. and Ph.D. degrees in Computer Science from Universidad Politeˇcnica de Madrid. Her current research areas include database modelling and design, object oriented analysis and design, datawarehouses, and software engineering. She has published several technical articles and books, and worked as program committee member in conferences and workshops. She was Computing Centre Director and Data Bank Director at INE (Spanish Statistical Office). Director or participant in some research and development projects (DELFOS, EINSTEIN, IRO-DB, METRICA, ...). Consultant on Data Bank at some international organisations in different projects (MECA -ATN/SF, UN/TCD, IBM, PII ŠUNESCO, etc.).

Elena Ferrari is an assistant professor at the Department of Computer Science of the University of Milano, Italy. Elena Ferrari received a MS degree in Information Sciences in 1992 from the University of Milano and a PhD in Computer Science in 1998 from the University of Milano, Italy. She has also been a visiting researcher at George Mason University, Fairfax (VA) and at Rutgers University, Newark (NJ). Her main research interests include: database security, multimedia databases and temporal object-oriented data models. On these topics, she has published several papers. She has served as a PC member of the 1997 International Workshop on Multimedia Information Systems.

Giovanna Guerrini is an assistant professor at the Department of Computer and Information Sciences of the University of Genova. She received the MS and PhD degrees in Computer Science from the University of Genova, Italy, in 1993 and 1998, respectively. Her research interests include object-oriented, active, deductive and temporal databases, semi-structured information.

Gerti Kappel is a full professor of computer science and head of the Department of Information Systems at the Johannes Kepler University of Linz since 1993. She received the Ms and PhD degrees in computer science from the University of Vienna and Vienna University of Technology in 1984 and 1987, respectively. From 1987 to 1989 she was a visiting researcher at Centre Universitaire d'Informatique, Geneva, Switzerland. Her current research interests include active object-oriented database systems, object-oriented software engineering, dataweb technology, and applications to workflow management and electronic commerce. She has been involved in national and international joint projects between the university and industry applying database and object-oriented technology to non-standard applications. Dr. Kappel is a member of ACM, IEEE, GI, and OCG.

Isabella Merlo received a MS Degree in Computer Science (with honours) at the University of Genova in 1996. Since November 1996, she is enrolled in a PhD program, under the supervision of Prof. Elisa Bertino, in the Department of Computer and Information Sciences of the University of Genova as a member of the Databases and Information Systems Group. Her current research interests include object-oriented, active and temporal databases, data models for management of semi-structured data.