Combining theory and practice, this book presents arguments and analyses using first-hand data from the 2010 National Sample Survey of the Elderly Population, the Survey on Changes in Family Structure and Intergenerational Relationships in China and the Survey on New Rural Pension Insurance in 20 provinces, autonomous regions and municipalities directly under the Central Government of China, which were conducted by the authors concerned. Innovative ideas and methods are presented. Based on the standard consumer theory, a model of the effective demand and marginal propensity to consume of the elderly population is constructed to explain the different trends of the propensity to consume of the elderly population in China around 2020; the timing of Lewis' first and second inflection points in China is specifically analysed to clarify the theoretical basis and practical feasibility of reducing excessive reliance on labour for economic development and accelerating the substitution of capital for labour; ageing and urbanisation are synchronised and the problem of rural ageing is highlighted. In the face of ageing and social transformation, it is important to explain how to systematically protect the rights and interests of the elderly population in terms of property, equality and remarriage after widowhood; to achieve the goal of "basic, extensive, flexible and sustainable" old-age security, which can be achieved in accordance with strict The "New Farmers' Insurance" pilot scheme has been rolled out on a large scale, and the latest survey data from 20 provinces, autonomous regions and municipalities are used to analyse and propose options for overcoming the difficulties of full coverage. The latest survey data from 20 provinces, autonomous regions and municipalities have been used to analyse and propose options to overcome the difficulties of full coverage.