In this paper we explore some key antionomies which have emerged in relation to children and childhood in late modernity: tensions between autonomy and protection and between perceptions of children as ‘at risk’ and as potentially threatening. A particular focus here is on the sexualisation of risk, the degree of public concern expressed whenever the sexual ‘innocence’ of children is thought to be endangered. We argue that the concept of risk anxiety provides a useful means of analysing contemporary fears about children and childhood and may thus be understood as contributing to the ongoing social construction of childhood. Here risk anxiety must be located within the context of gendered and generational power relations, in which children’s lives are bounded by adult surveillance. Furthermore, risk anxiety may have material consequences for children’s daily lives and for everyday adult–child negotiations around safety and danger, protection and autonomy.