Massive bilingual corpora which can now be compiled with the available computing facilities are particularly relevant to conduct linguistic research in translation studies. The corpus of legal documents of the European Acquis have been aligned and investigated with two software packages, ALINEA and PARACONC. These corpora once aligned provide translation memories and terminology databases for a given field. Dealing with legal and technical documents in which recurring passages are frequent, professional translators improve the consistency and productivity of their production significantly.