Educational inequalities are evident even before children start school. Some educational achievement gaps widen out as individuals progress further through the education sequence and into the labour market, especially those connected to disadvantaged students. Thus, there is a significant need for careful evaluation of educational policies that are designed to try to affect inequalities in education. The authors document various forms of educational inequality. They then review available evidence for England about the impact of school-level policies on achievement and their potential for reducing the socio-economic gap. Finally, they discuss evaluation evidence under four main themes: school resources; market incentives; school autonomy; and pedagogical approaches. (Contains 3 figures, 1 table and 18 footnotes.)