This paper concerns the reuse of engineering components in design, and a method of finding them for non-standard applications, leading to reduced costs in low-volume production. This retrieval task is a basic instance of finding more generalized fragments of design knowledge. The paper presents an architecture for managing access to component catalogues, allowing designers to find components on the basis of their intended use rather than a pre-defined indexing scheme. Placing this retrieval tool on the Web provides a natural alternative to the current arrangement of distributing successive manufacturer-specific catalogues and searching them via one or more indexes.