The research project analyses Portugal's participation in PISA. This analysis seeks to understand the reasons Portugal is depicted by the OECD as a success case, with one of the most significant evolutions in results between 2006 and 2015. Assuming that these international surveys, particularly PISA, constitute powerful transnational regulation means, the research project covers several dimensions of analyis, attempting to know how the different national actors (policy-makers, school administrators, teachers' unions, parents) associations, media) have appropriated the process and included the results of this participation in discourses, public policies and professional practices.