Kara Warburton will present a summary of her research investigating the terminological data in terminology databases (termbases) and in corresponding corpora from four commercial sources. She will demonstrate that there are significant gaps between the termbases and the corresponding corpora, that such gaps reduce the effectiveness of the termbases, and that they can be minimised by adopting a corpus-based approach to term identification. Her findings raise questions about conventional definitions of the notion of termhood.