A method and program product for integrating different data sources has steps of obtaining semantic information from each of the different data sources (200, 202, 210), creating a conceptual model of (218, 220, 22) the data source using the semantic information, and accessing one or more secondary knowledge sources. The secondary information sources contain information regarding the relations of data from different of the databases, so that an integrated semantic model of all of the databases (200, 202, 210) may be created. Queries can then be processed using the integrated semantic model.