There has been little research exploring pupils' satisfaction with their ability group placement. This article explores the extent to which pupils are happy with their placement, and the reasons they give for wanting to move to another class or set. The sample comprised over 5000 Year 9 pupils (aged 13-14 years) in 45 mixed secondary comprehensive schools in England. The schools represented three levels of ability grouping in the lower school (Years 7 to 9). Pupils responded to a questionnaire which explored their current set placement, their satisfaction with it, and their reasons for wanting to change. A substantial proportion of pupils expressed a wish to change set, most, but not all, in an upward direction, mainly because the level of work was inappropriate. The implications for ability grouping practices in schools are discussed. (Contains 6 tables.)