The General Agreement on Trade in Services (GATS) of the World Trade Organization has generated an intense and passionate debate about the relationship between free-trade and education and, specifically, about the effects of trade liberalization in national education systems. This article explores in detail this debate from a critical discourse and semiotic approach. Its objective is two-fold. First, it aims at identifying and systematizing the core axes of the debate, as well as at confronting ideas within each of the axes. Second, it aims at explaining how and why the agreement has generated such an intense and polarized discussion in the educational field by, among other analytical strategies, appealing to the broader institutional and ideational contexts in which the debate is inscribed. Arguments are based on observation in public debates on GATS and education and a corpus of 86 texts on the topic coming from different sources including academic journals, conference proceedings, policy reports and newsletters of international and civil society organizations. (Contains 7 notes.)