Chapter 22 Income and Peer Quality Sorting in Public and Private Schools Any system of primary and secondary schools involves explicit or implicit mechanisms that ration not only financial but also nonfinancial inputs into education production. This chapter focuses primarily on such mechanisms as they relate to the sorting of parents and children into schools and classrooms. Three primary mechanisms are reviewed: (1) sorting that emerges through residential location choices within housing markets that are linked to schools; (2) sorting that arises from parental choices to send children to private rather than public schools; and (3) sorting within schools that results from explicit tracking policies. The equilibrium level of sorting (along parental income and child peer quality dimensions) then depends on both the specifics of how education production works and the overall characteristics of the general equilibrium environment within which schools operate. We review the theoretical as well as the related simulation based literature in this area and suggest that much potential exists for increasing empirical relevance of the emerging models for policy analysis particularly as a related empirical literature comes to better terms with the nature of peer effects in education production.