Children and young people’s participation in collective decision-making has become a popular policy and practice concern. Yet challenges persist, such as tokenism, limited impact and unsustainability. This article examines ways to address these challenges and realise children and young people’s participation, particularly in child protection contexts. Conceptually, the article investigates three popular ideas – vulnerability, social accountability and co-production. Each idea potentially suggests revised and more emancipatory relationships between the State and service users. Practically, the article matches these ideas to examples of children and young people’s participation. The article concludes that claims to vulnerability’s universality are persuasive; however, conceptualisations fail to address adult power. Social accountability addresses power, but insufficiently addresses the current challenges of participation. Co-production has the most potential, with participation examples that have been meaningful, effective and sustainable.