The difficulties in the translation of formulaic expressions, then, lie (a) in their identification as formulaic, which implies that they cannot be translated into the target language by routine methods, (b) in knowing what they mean in the source text, and (c) in adequately rendering them in the target language. Therefore, I have formulated a working definition and classification and compared the number of formulaic expressions both in the source text (English) and target text (Spanish) and the way they have been translated into the target language (or remain untranslated). This study is both qualitative and quantitative, as I will also look at any possible errors or omissions in the target text. By analysing the way translators deal with the formulaic expressions in our corpus of specialized texts, we draw conclusions and derive guidelines for good translating practice and translating practices to avoid when dealing with formulaic language in instruction manuals. Some possible reasons are established as to why a formulaic expression was used in the first place and the role it plays within the text. Though it is likely that the scale of this study is too small to make it fully representative of the phenomenon of formulaicity in specialized domains, interesting insights are expected to emerge that may be used in future studies.