This paper considers how varying discourses of social exclusion have informed policies regarding young people's participation in education, training and employment. Drawing on a cohort study of over 800 16–18 olds, the research suggests that the binary categories of exclusion/inclusion, and marginalisation/participation grow less and less adequate as parameters for understanding changing patterns of post-16 participation and non-participation. It is argued that a range of statutory, structural, financial and social pressures to normalise participation produce forms of inclusion that are ephemeral and that carry very different meanings from those implied in discourses of exclusion. The paper gives a brief overview of the changing context in which participation needs to be understood, then presents evidence and analysis of young people's trajectories after 16. Some interpretations are offered of a wide range of meanings of participation, which suggest that old notions of transition to independence are unsustainable for a substantial minority of young people, and that patterns of participation are increasingly complex, have multiple significances, and carry the potential to mask inequalities and new forms of exclusion. These readings have major implications for how we conceptualise social exclusion, and for policy developments associated with it.