On the surface, exclusion from school is a puzzling phenomenon. Policy emphasises inclusion, participation, the importance of education and skills, and yet each year thousands of vulnerable young people are excluded from school. This paradox is at the heart of this chapter where school exclusions are considered against a broader background of public policy. The practice of exclusion from school, and the patterns evident in exclusion statistics, are both used to probe policy frameworks which foster social inclusion. But exclusion from school also has meaning for those who are excluded and their families, and for those who administer exclusions. This policy analysis is related to the experience of those most closely involved and affected by exclusion, using interview data from pupils, local authority (LA) officers, headteachers and policymakers.