One quarter of the 1958 British Birth cohort attended single-sex secondary schools. This paper asks whether sex-segregated schooling had any impact on the experience of gender differences in the labour market in mid-life. We examine outcomes at age 42, allowing for socio-economic origins and abilities measured in childhood. We find no net impact of single-sex schooling on the chances of being employed in 2000, nor on the horizontal or social class segregation of mid-life occupations. But we do find a positive premium (5%) on the wages of women (but not men), of having attended a single-sex school. This was accounted for by the relatively good performance of girls-only school students in post-16 qualifications, not by the wider range of subjects studied by both girls and boys at single-sex schools. Men's labour market attainments were more closely related to attending private schools and to parental class, suggesting that the intergenerational transmission of advantage, while not related to coeducation, is related to gender. (Contains 7 tables and 2 figures.)