Electronic catalogues are a major tool for developing Electronic Commerce (EC) applications. From a customer’s perspective, however, the variety and heterogeneity of electronic catalogues create a major problem in integrating information from various sources. There have been several attempts to overcome this problem using architectures and protocols that enable interoperabilty of electronic catalogues. The extant architectures and protocols emphasize semantic integration of different catalogues as a mean for achieving interoperability. In this paper we expand the previous work on this topic by proposing a comprehensive agent-based conceptual model of an Intelligent Catalogue Search System (ICSS). The ICSS incorporates knowledge in order to analyze, enhance, filter and synthesize a raw query and replies provided by various electronic catalogues or intercatalogue search systems. The benefit of the proposed architecture is an increase in the capability of a customer to locate and compare relevant products from various sources.