The objective of this study is to analyse the determinants of thequality of education in Argentina and, in particular, to look at what influencea school's ownership structure has. A multilevel regression model and2006 data from the Programme for International Student Assessment(PISA); were used for this purpose. One of the main findings is that thecorrelation between a school's administrative structure (public or private);and its students' scholastic performance fades when the socioeconomicschool environment is taken into consideration.