Research conducted by Patrick Clancy and by Fitzpatrick Associates and Philip O'Connell on the level of representation of socio-economic groups amongst higher education entrants has been a key element in the development of access policy and practice in Ireland. This article reviews the context for the development of access and explores the relationship between this research and access policy and practice. The research dominated access discourses and it is suggested that a risk of a reliance on such research is that it is seen as unproblematic and that categorical approaches are viewed as the only approach with which to conceptualise the relationship between disadvantage, social class and access to higher education. (Contains 4 tables and 3 notes.)