TERMINFO: At the Boundary between Terminology and Information Models The problem of using vocabularies in real-world contexts forces the question as to where vocabulary models, including composition, overlaps with information models in an application. As an example, these issues are particularly acute when considering how the SNOMED-CT context model fits within the HL7 V3 messages derived from the RIM. Parallel issues emerge across the spectrum of biomedical data and knowledge, from pharmacogenomics to functional status measures that involve the Gene Ontology, drug classifications, models of anatomy concepts, functional objects from NCI’s caBIO, and physiologic pathways as components of systems biology in addition to many others. An initial meeting was convened at NASA facilities in Houston in August 2004 to address the boundary problem between vocabulary and information models, with particular emphasis focused upon SNOMED-CT and HL7. The deliverables from this meeting are gratifying, and available at www.terminfo.org. We are proposing a general continuation of the informal interest group that has risen up around this problem by holding an evening workshop at MedInfo (Wed, 6pm; Hilton, Union Square 15 and 16). The initial meeting will be reviewed, further actions planned including follow-up meetings and a potential special journal issue on the topic.