The voucher scheme introduced in Chile in 1981 allows for-profit private subsidized schools to choose their students. This study examines the effects of this practice on the results’ gap between private and public schools and its impact on academic performance. Information from the 2005 SIMCE test is used, in which parents were asked about the admission requirements in their children’s schools. We present evidence indicating that student selection is a widespread practice among private subsidized schools. After controlling for a series of selection criteria and the segmentation effects that they produce, theevidence indicates that there are no differences in results between public and private subsidized education. Our results show that a student attending a school that uses selection criteria obtains 6-14% higher results in standardized mathematics tests than a student from a school that does not use selection.