In this thesis, the requirements of a children’s rights-based approach to regulating child and adolescent sexuality are explored, with a particular focus on the need to take into account both the vulnerability and autonomy of children and adolescents as subjects of sexual and reproductive rights. The ‘[r]egulation of child and adolescent sexuality’ is understood as all legal norms determining the conditions under which young people live their sexuality. The analysis is focused on three areas where the tension between the protective and emancipatory dimensions of law is particularly significant: sexuality education, reproductive health and criminal laws on sexual assault. The approach is a doctrinal one and combines an analysis of applicable international norms with a comparative study of four national legal systems, namely England and Wales, France, Ireland and Poland. An argument is presented in this thesis that sexual and reproductive rights, as currently defined in international law, must be adapted to the particular needs of children and adolescents as rights-holders. To this end, key concepts and principles of the United Nations Convention on the Rights of the Child, such as the best interests of the child, the child’s evolving capacities, the concept of parental direction and guidance, the prohibition of discrimination and the right to be heard, are critically examined in order to create understanding of how they can be applied to the area of sexuality and reproduction. The analysis of the framework established by the Convention reveals that it cannot provide a solid theoretical foundation for such an adaptation. This is mostly due to the Convention’s failure to affirm and properly conceptualise the child’s legal capacity and its implications for the autonomous exercise of rights, which has never been properly addressed by the United Nations Committee on the Rights of the Child in its interpretative work. These deficiencies of the Convention framework result in the limited impact of international standards on national laws identified in the present comparative study.