The labour supply of teenagers in full-time education has been largely neglected in analyses both of the UK youth labour market and of educational decisions and policy. The teenage years have been seen as when a single transition takes place from full-time education to employment (or unemployment), in the form of a ‘school-leaving’ decision. The possibility that the transition from school to work may be more gradual, and involve a phase when school and work overlap, has been less discussed. Yet there are indications that the part-time work of teenagers in full-time education is a far from trivial aspect of teenage labour supply; an analysis of data from the Labour Force Survey for autumn 1992 (Sly, 1993) found that about one third of 16 and 17 year olds in full-time education also had a job, and that there were as many 16 and 17 year olds in full-time education who had jobs as there were school-leavers in work in the same age group.