A more intuitive, easy and powerful representation, access, and retrieval of information is nowadays a necessary feature of information systems that have become a common instrument for a wide class of users in di?erent areas and for the most diversi?ed tasks. The management of imprecision and uncertainty in databases has become an important research area, which has known an impressive growth. This is testi?ed the increasing number of special sessions in international conferences and workshops devoted to this theme. Generally, this topic matured and developed independently within both the...

The International Conference on E-commerce and Web Technologies (EC-Web) is a mature and well-established forum for researchers working in the area of electronic commerce and web technologies. These are the proceedings of the ninth conference in the series, which, like previous EC-Web conferences, was co-located with DEXA, the International Conference on Database and Expert Systems Applications, which, this year, took place in Turin, Italy. One key feature of EC-Web is its two-fold nature: it brings together both papers proposing technological solutions for e-commerce and the World Wide Web,...