This article describes a participatory research project, which explored four case studies of children and young people's successful political advocacy in Nicaragua. The analysis combined a human rights-based approach and a human development approach, and included concepts of multiple settings and levels, interrelated participation spaces, children and young people's citizenship, inclusion and exclusion, democracy, advocacy and empowerment. The main problems faced by children and young people seeking to influence policy-makers were identified as adultism, dependency and lack of accountability. The research identified pre-conditions, participation spaces and ways of organising for effective advocacy, and facilitation methods that had proved effective. It concludes that children and young people who achieve effective advocacy are generally self-empowered, but can count on effective adult support and facilitation. They work through coordination with the authorities and not by clashing with them, but need to ensure effective follow up if they want politicians to keep their promises.