The allocation of teacher competence is frequently cited as a determinant of socioeconomic inequity in student outcomes. This thesis explores several aspects related to the phenomenon of ‘teacher sorting’ from a cross-national perspective. It aims to empirically validate theoretical questions regarding social reproduction and the allocation of educational resources, as well as whether inequitable allocation contributes to socioeconomic gaps in student performance. The thesis presents four empirical studies with two pairs of related research questions. Study I examined the magnitude of teacher sorting across education systems and over the past 20 years. Study II extends this line of questioning and examines whether the sorting gap magnitudes exacerbate mathematics achievement inequity within countries. Studies III and IV examined whether institution- level policies are associated with several different dimensions of teacher sorting. The findings lend partial support to the role of inequitable teacher competence in perpetuating inequitable student outcomes, but also point to the importance of the socioeconomic context and construct measurement in considering inequity and policy across education systems.