When adopted in 1989, the Convention on the Rights of the Child (CRC) enshrined, for the first time in international law, the recognition of children as subjects of the full scope of civil, political, economic, social, and cultural rights, a culmination in the evolution of the concept of childhood and a paradigm shift from the perception of children as the property of their parents. Since then, the Convention became the most ratified international human rights treaty in history and has prompted deep, transformative changes for children across the world, including with support from the United Nations (UN). More children than ever before now have access to health, education, protection, and participation opportunities. Yet, child rights today are often misunderstood, disregarded, or disputed. Despite progress across all regions, children – i.e., all human beings under 18 – are still largely regarded as the objects of adults’ goodwill; mere recipients of services; or solely as a “vulnerable group”, rather than individual subjects of rights and empowered agents in the exercise of their rights. A normative pushback against child rights is taking place globally, including in intergovernmental fora, threatening to undermine the integrity of international standards pertaining to children – for example in relation to gender or civil and political rights. Across the UN system, the rights of children – who make up 30% of humanity – are not systematically considered in system-wide or entity-specific policies, strategies and approaches and are generally seen as the exclusive responsibility of a few entities. Against this backdrop and with this guidance note, the Secretary-General of the UN mandates the mobilization of the UN system to collectively strengthen and elevate a shared UN child rights agenda. Systematic attention to child rights is necessary for the UN to be fully inclusive and able to deliver on its mandate across all pillars, including upholding “all rights of all people”, achieving the Sustainable Development Goals (SDGs) and ensuring peace and security. The multiplicity of crises disproportionately affecting children in the world today – armed conflicts, natural disasters, climate change, growing poverty, shrinking civic space, increased migration, persisting inequalities and the impact of Covid-19 on social protection, education, health, nutrition, mental health and psychosocial wellbeing, violence and exploitation – adds urgency to this necessity.