This technical document represents a comprehensive evaluation of publicly available information on front-end uranic inventories, while considering the approach of end users towards the reliability of their once-through supply chain. Country/regional detail is provided for Africa and the Middle East; Eurasia; Europe; North America; South America; South and East Asia. This approach, rather than simply a global view, better reflects the realities of local market supply and demand conditions in 2021 for nuclear fuel. The research can therefore help inform strategies for the assurance of nuclear fuel supply for the safe and secure operation of nuclear power plants. The publication is intended for all IAEA Member States with nuclear power, and IAEA Member States that are considering the development of nuclear power and are interested in security and assurance of nuclear fuel supply.