The long-term effects of secondary-school reforms in the first half of the 20th century are investigated through the long-term follow up of a sample of people born in Scotland in 1936 who were first surveyed in 1947. Members of the sample who were living in the Lothian region of Scotland were re-interviewed in 2004-2007, providing information about their occupational status and educational achievement. The occupational status and educational attainment of respondents' parents were collected in the follow up, as was information about school attended by respondents. Respondents completed the same intelligence test as they sat in 1947. The main research question is whether attempts by policy makers in the early 20th century to widen access to secondary schooling had long-term effects on the social distribution of educational and occupational opportunities.