The population age structure is critical for the socio-economic development of countries. A large working age population provides countries with a window of opportunity to accelerate economic growth through increased productivity, savings and investments. As early as 2007, the African Population Commission highlighted the importance of the demographic dividend and devoted the 2012 State of Africa Population Report to “Harnessing the demographic dividend for the socioeconomic development of Africa.” Thereafter, other high-level regional meetings also called for recognition of the demographic dividend in Africa’s development efforts. In 2016, the Africa Union (AU) Assembly made the decision to develop a continental roadmap for harnessing the dividend and countries were urged to domesticate and operationalize the AU Roadmap. This decision led to the development of the AU Roadmap on Harnessing the DD through Investments in Youth in 2017. Many countries in the Eastern and Southern Region (ESAR) have developed demographic dividend (DD) profiles and are implementing policies to harness the DD. This report assesses the performance and identifies best practices among ESAR countries in operationalising the DD through the translation of demographic intelligence into national development plans, visions and decision making to harness the DD. The assessment employed multiple qualitative approaches including; review of policies and development plans, administration of a survey to UNFPA Population and Development (P&D) advisors and in-depth interviews with various stakeholders in 9 selected ESAR countries. Our findings show five key areas that countries must focus on in the DD implementation process; advocacy, generation of continuous evidence to inform and guide implementation process, integration of DD into national development plans and strategies, multi-stakeholder collaboration and coordination, and development of a monitoring and accountability framework to assess and course-correct the process.