National Transfer Accounts (NTA) provides a coherent accounting framework of economic flows from one age group or generation to another, typically for a national population in a given calendar year. This manual consolidates and presents in a systematic fashion the concepts, the methods and estimation procedures to measure these flows of resources across age. The NTA estimates are useful to understand and analyse inter-generational economic flows, and the implications of changing population age structures for the fiscal sustainability of social programs, the accumulation of physical and human capital, macroeconomic growth, and familial support for children, youth and older persons.