This report, commissioned by Save the Children Child Rights Governance Initiative (CRGI), provides evidence for the organisation’s CRGI, in particular its global breakthrough on Investment in Children. It looks at reasons to invest in children, focusing on rights, economic and political arguments, using a ‘continuum of financing’ approach which looks at public spending, the creation of fiscal space and economic growth. States that have ratified the UN Convention on the Rights of the Child (UNCRC) have taken on obligations to implement these rights ‘to the maximum extent of their available resources’ and, where necessary, to seek international cooperation to support the fulfilment of these rights. As the main duty bearer in the fulfilment of children’s rights, the state plays a critical role in generating an enabling environment to do this. It can best foster this through the development of a context-specific, child-sensitive policy framework based on evidence of aspects of child rights that are identified to be lacking or that remain unfulfilled.