Upper secondary education has been identified by different institutions as the minimum educational threshold in a knowledge society, a necessary requirement for citizens of all ages to respond to the social changes driven by global technological innovation. Figures from the Organization for Economic Cooperation and Development (OECD) unfortunately show that a large share of adult population in OECD countries still lack upper secondary qualifications. Italy appears in these statistics as one among the lowest ranking countries and provisions currently in place to bring adult citizens back to school still yield quite low numbers. This research aims at exploring the challenges to adult students' participation in upper secondary education in Italy examining the actual experience of a group of grown-up learners attending a public vocational school. The results of the inquiry are based on the analysis of semi-structured interviews framed in a qualitative research design. The study is grounded in a theoretical frame derived both from participation theories and from the capability approach. The main conclusion of the research is that successful participation and persistence in adult education require students’ expectations to be appropriately met by an attentive customized institutional support. To this respect, the research suggests recommendations in order to improve public information about provisions for grown-up students, to separate adult education from second chance teenage schooling and to customize adult learning through appropriate learning management tools.