This article summarises research from Smithfield Project, a large longitudi
nal study of markets in education which tracked the impact of the school ch
oice policies oil schools, students and their families in two New Zealand c
ities between 1992 and 1997. After considering the arguments of the propone
nts and critics of educational markets, the article examines questions abou
t who gets to choose in the educational market place and the impact of thos
e choices on school composition, as well as the effects of school compositi
on on student achievement. It is argued that choice in educational markets
is determined by social class and ethnicity and that, as a consequence, mar
kets polarise school intakes and lead to the decline of working class schoo
ls. Those schools which lose a well balanced social class mix of students w
ill also suffer a decline in their performance. Some policy implications of
the study are discussed.