A multidatabase system is an effective approach to implement data sharing and interoperability among many distributed and heterogeneous data sources. In this paper, a CORBA-based architecture model of multidatabase system is firstly introduced. Then, an XML-oriented common data model, named XIDM, is presented. These models conform well to the characteristics of multidatabase systems such as autonomy, distribution and heterogeneity. Panorama, a prototype system implemented based on these models, is introduced at the end of the paper. 1