The authors contend that children from lower socio-economic status homes are systematically discriminated against in the delivery of school services. Data from Michigan are employed to demonstrate that state aid equilization arrangements not only do not alleviate this discrimination, but, in fact, actually tend to reinforce it. James W. Guthrie is an Assistant Professor and Director of the Urban Education Program at the University of California, Berkeley; George B. Kleindorfer is a Lecturer in the School of Education, University of California, Berkeley and a Consultant to the Ford Foundation on matters related to quantitative analysis: Henry M. Levin is an Associate Professor in the School of Education and a member of the associated faculty of economics at Stanford University; and Robert T. Stout is an Associate Professor at the Clairmont Graduate School and the Coordinator of the Ford Foundation-funded Administrator Training Program at that institution.