Uranium is the raw material used to produce fuel for long-lived nuclear power facilities, necessary for the generation of significant amounts of low-carbon electricity and other uses, such as heat and hydrogen production, for decades to come. Although a valuable commodity, major producing countries limited total production in recent years in response to a depressed uranium market. Uranium production cuts have unexpectedly deepened with the onset of the global COVID-19 pandemic in early 2020, leading to some questions being raised about future uranium supply. This 28th edition of the “Red Book”, a recognised world reference on uranium jointly prepared by the Nuclear Energy Agency (NEA) and the International Atomic Energy Agency (IAEA), provides analyses and information from 45 producing and consuming countries in order to address these and other questions. The present edition reviews world uranium market fundamentals and presents data on global uranium exploration, resources, production and reactor-related requirements. It offers updated information on established uranium production centres and mine development plans, as well as projections of nuclear generating capacity and reactor-related requirements through 2040.