This paper argues that even though there is continuous research work on participation in adult education, the current state of research is not satisfactory. It develops this assumption by discussing studies that focus on social status and social milieu as explanatory factors for adult education. The authors draw on findings from a research project on social space and adult education as the basis for arguing that the category of space cannot be neglected in explaining participation, as well as developing cornerstones of a research programme based on analyses which theoretically and methodologically integrate perspectives which have thus far been researched separately. (Contains 1 note and 11 tables.)