The present study sought to determine to what extent vestiges of the dual system of educating students with and without disabilities persist and how they undermine the implementation and sustainability of inclusive education. We investigated how prior experiences with segregation shape administrators' thinking and school policies and practices through interviews with administrators in 11 public high schools. Analysis of the interviews indicated that remnants of past policy and practice persist and that these vestiges and their causes weaken the prospect of sustained change. We discuss the limitations of relying on legislation to change long-standing institutional practices that reinforce a philosophy of difference. (Contains 2 tables.)