The paper defines education markets based on the major divisions in the school system like public-private, tracking either by curriculum or by ability, and schools' practice regarding admittance of students. These segments in the school system create a "market", put the schools into various positions in the educational "field", and parents consider these options when deciding about school choice. Furthermore, school's position in the market has an impact on students' performance even if controlled for school composition. This paper analyzes 23 OECD countries from the PISA 2006 survey. The results indicate that high-status families prefer more selective schools with the exception of ability tracking. Moreover, the more selective schools perform better, but ability grouping does not improve achievement. Applying interaction terms shows that religious schools are able to compensate the disadvantages of pupils coming from low-status families at most. (Contains 7 tables and 1 note.)