The United Nations (henceforth: UN) provide not only a legal-policy framework for public participation of children and youth, but it enhanced empowered spaces through ‘youth constituencies’ affiliated with UN agencies and conferences in sustainable development areas (including environment and climate change). In this chapter, a historical mapping starting from 1992 (the year of institutionalisation of public participation of children and youth in the UN) provides an overview of the international governance structure and the way youth constituencies function. Despite the political will, there is vast evidence that the reality paints a strikingly different picture: children are practically not invited, or merely for highly tokenistic (greenwashing) purposes at UN high-level negotiations on climate change. Instead, their interests are represented by child-rights organisations and/or the youth groups. Moreover, ‘youth’ (young adults) as stakeholders face similar constraints to meaningful (inclusive and impactful) participation despite that their involvement in conferences is more prevalent. This insight does not dwell on the hardships though: it also seeks to find answers to why the age-group of ‘youth’ have gained space over children while assenting the role of representing them, and whether the depreciation of people under 18 years in these empowered, former settings force children as climate citizens to discover alternative pathways (such as grassroots movements or litigation) to influence climate change governance.