The proposed project focuses on the quality of the selection of students from primary school in order to assign them to different tracks in secondary school in Luxembourg. It is a matter of fact that this quality strongly affects not only the career of these students in their professional life, but also—as an additional result—the development of economic and social wealth in Luxembourg.First, we aim at reviewing the actual quality of Luxembourgish school placement decisions by relating these decisions to different school success parameters across several grades and various age-groups of students. Second, we will extend existing data bases containing school placement decisions and school success parameters in order to allow for longitudinal analyses of the predictive validity of school placement decisions. Third, we intend to develop alternative measurements of predictive validity which would overcome methodological weaknesses of prior approaches. Forth, we will identify conditions that might raise or weaken the predictive validity of school placement decisions made in Luxembourg. Fifth and finally, we are looking for factors that might predict school success even better than school placement decisions. Thus, at the end of the proposed project we will be able to judge in how far school placement decisions reflect students abilities, and whether school placement decisions should persist the way they currently are made, or should better be replaced by other forms of selection processes.