Epic is an image retrieval system that implements a novel spatial-querying mechanism. A usercentred, task-oriented, comparative evaluation of Epic was undertaken in which two versions of the system--one set up to enable spatial queries only, the other allowing textual queries only-were compared. Use was made of the two systems by design professionals in simulated work task situations, and quantitative and qualitative data collected as indicators of the levels of users’ satisfaction. Re sults demonstrated that users often had a ‘mental image’of a potentially satisfying picture in mind, that they were happy to express this need in visual terms, and that in doing so they preferred to have access to Epic’s spatialquerying facility. Success in obtaining statistically significant results appears to support validation of the novel methodological framework adopted.