Despite the fundamental importance of childhood, countries tend to invest much less in this area than in old age. Effective child well-being policies can bring high long-term returns on early life investments and public interventions. However, these benefits are not fully understood and thus do not always receive the necessary political attention in public policy making. Mobilising evidence to support effective policies for child well-being is crucial, especially as responsibilities for such policies tend to be fragmented across government departments and levels of government. Therefore, organisations such as knowledge brokers, which help ensure that evidence is shared with those responsible for designing and implementing public policies, have a critical role to play in improving the effectiveness of child well-being policies and practices. They can help make evidence accessible, trustworthy, and understandable, so that it has the greatest impact on policy. This working paper sheds light on the best practices identified for mobilising evidence to enhance the effectiveness of child well-being policies, based on a stocktaking of 81 knowledge broker organisations across 24 countries, complemented by a qualitative survey carried out among senior experts operating at national and international level.