This article focuses on student admissions to charter schools in the United States and to autonomous (foundation and voluntary-aided) secondary schools in England. Analyses of the admissions criteria used by autonomous and nonautonomous secondary schools in England revealed that more autonomous than nonautonomous schools reported using potentially selective criteria. Examination results were higher in autonomous than nonautonomous schools and even higher in those that used potentially selective admissions criteria. Fewer students with special educational needs attended autonomous schools. The similarities between the admissions practices used by certain charter schools and the published admissions criteria used by certain autonomous schools in England are discussed. The evidence is suggestive of both "cream skimming" and "cropping off" educational provision to particular groups of students. It is concluded that the introduction of market oriented reforms into public school systems requires monitoring and effective regulation to ensure that autonomous schools do not act in their own self-interest. (Contains 6 tables and 13 notes.)