Drawing on a logitudinal data set from a national sample of British children horn in 1946, this paper explains educational attainment of boys at age 21 in terms of social origin, ability, attainment of boys at age 21 in terms of social origin, ability, and type of secondary school attended. Both ability and social origin help to explain selection for type of secondary school. Attending one of the more elite forms of secondary school (grammar, technical, or private) is associated with higher levels of attainment, even with ability held constant. Formal qualificaitions, awarded according to universalistic standards, and opportunities for further education after leaving school type are tempered, but the effects are strong throughout.