Following a two day workshop, held in Lyon in 2004, this special issue aims at examining how current research in terminology engineering is influenced by particular target applications. The Lyon workshop showed that investigators from many disciplines (linguistics, information retrieval, knowledge management, philosophy, computational linguistics) use the notion of ‘term’ to refer to different text units with different morphological and syntactic properties. The special issue examines how an application (the end use to which the processed terms are destined) influences the choice of the text units and their processing. In such an application-oriented framework, ‘term’ designates the meaningful text unit in specialized discourse considered useful for an application. This approach can be expressed more simply as, “the application justifies the notion of ‘term’ and their choice”.