This collective volume on machine translation has three main parts: the introduction, which provides both historical and theoretical background and which is designed to provide an interpretive account of some of the major milestones in the field of MT but also to point out the problemes that had to be addressed; the second part is on MT architecture and related software issues; and the third section contains a partial survey of operational systems plus detailed presentations of seven specific ones, among which SYSTRAN and TAUM-METEO.