The LogoVista ES translation system translates English text to Spanish. It is a member of LEC’s family of translation tools and uses the same engine as LogoVista EJ. This engine, which has been under development for ten years, is heavily linguistic and rule-based. It includes a very large, highly annotated English dictionary that contains detailed syntactic, semantic and domain information; a binary parser that produces multiple parses for each sentence; a 12,000+-rule, context-free English grammar; and a synthesis file of rules that convert each parsed English structure into a Spanish structure. The main tasks involved in developing a new language pair include the addition of target-language translations to the dictionary and the addition of rules to the synthesis file. The system’s modular design allows the work to be carried out by linguists, independent of engineers.