Scientific-technical texts present a series of relatively simple morphosyntactic and stylistic characteristics. However their translation is very complicated. This is due to the presence of characteristics typical to this kind of text-pragmatical aspects and terminology. To carry out a good translation, these two obstacles must be overcome. Documentation is the translator's great ally. Only if this professional has a good management of the different kinds of documents in their different forms and if he has ready access to them, he will be able to accomplish a faithful translation with an adequate terminology.