After analysing various different argumentative texts written in Spanish, it is evident that the existing lists of discourse markers used need to be extended in order to incorporate noncatalogued units capable of bringing about semantic-pragmatic relationships between members of the discourse. The application of a solid theoretical framework revealed that the following expressions function as discourse markers, although they have not been recognised as such: se trata de (this is about), por asi decirlo (so to say), hablando de (speaking about) + nominal group, no olvidemos que (let's not forget that), de to que se colige/deduce que (it follows that) y at grano (straight to the point).