This text motivates and defines a generic model for interactive (online or offline) product catalogs. Based on a detailed requirements analysis, the data model is defined using an object-oriented design notation and the query language for expressing customer interests on the catalog is defined using techniques from fuzzy set theory. The model provides the basis for the implementation of a generic, highly-interactive catalog management system which is designed to be interfaced with relational databases, information-retrieval engines and special-purpose index structures.