This article explores social class and gender differences in entry to the two main higher education sectors, universities and institutes of technology, among school leavers in Ireland over the period 1980-2006. A rational choice perspective is adopted, with participation hypothesised to reflect the costs and benefits attaching to attending the two types of institution. The initial expansion of higher education resulted in a widening of the participation gap between the higher professional and other groups, with some reduction thereafter as higher professional groups reached near-saturation levels. The removal of higher education tuition fees in 1996 was not sufficient to increase working-class participation in a context where other direct costs remained high and employment represented an attractive option. The period analysed saw a significant shift in the gender composition of higher education entrants, with young women now making up the majority. This article points to the value of taking a dynamic approach to analysing higher education participation, unpacking the effects of expansion in provision and of the costs and benefits attached to higher education entry.