The aim of this study was to examine trends to upward social mobility among a specially selected group of people with above average intelligence. This is a continuous survey, but this dataset is the only wave held at the Data Archive. Attitudinal/Behavioural Questions Reasons for joining Mensa, whether membership of Mensa raised occupational ambitions, job preference. Questionnaires were also completed by respondent's immediately older and immediately younger siblings. Background Variables Age, sex, marital status, number of children, whether father still alive (if dead: respondent's age at death), position in family, size of family. Occupation (respondent, parents and siblings - mother's occupation before marriage), years of part-time education, highest qualification, word score, gross income. Religious affiliation, political support.