Contemporary picture archiving and communication systems are limited in managing large and varied image collections, because content-based image retrieval (CBIR) methods are unavailable. In this paper, an XML-based data and resource exchange framework is defined using open standards and software to enable specialized CBIR systems to act as geographically distributed toolkits. The approach enables communication and collaboration between two or more geographically separated complementary systems with possibly different architectures and developed on different platforms, and specialized for different image modalities and characteristics. The resulting synergy provides the user with a rich functionality operating within a familiar Web browser interface, making the combined system portable and independent of location and underlying user operating systems. We describe the coupling of the Image Retrieval in Medical Applications (IRMA) system and the Spine Pathology and Image Retrieval System (SPIRS) as proof of this concept.