An RTD project funded by the European Commission under the IST Programme. The aim of TT2 is to develop a Computer-Assisted Translation (CAT) system, which will help to meet the growing demand for high-quality translation. The innovative solution proposed by TT2 is to embed a data-driven machine translation engine with an interactive translation environment. In this way, the system combines the best of two paradigms: the CAT paradigm, in which the human translator ensures high-quality output; and the MT paradigm, in which the machine ensures significant productivity gains. Another innovative feature of TT2 is that it will have two input modalities: text and speech. Six different versions of the system will be developed for English, French, Spanish and German. To ensure that TT2 corresponds to the translators’ needs, two professional translation agencies will evaluate successive prototypes.