Advocates argue that vouchers can make improved educational opportunity available to disadvantaged students. Critics contend that vouchers increase the risk of stratification. Researchers have found that Chile's voucher program has lead to increased socioeconomic school segregation. What has been overlooked, however, is segregation between schools within a sector and variation within private for-profit and non-profit school sectors. I find that public schools are more likely to serve disadvantaged students than private voucher schools. I also find that disadvantaged students are more segregated among private voucher schools than among public schools. While between and within sector segregation levels vary across private voucher school types, the differences are not always consistent with theory. The data also suggest that policies can either mitigate or exacerbate the stratifying effects of educational vouchers. (Contains 1 figure and 12 tables.)