Our societies are ageing. The Family is changing. Labour force behaviour is evolving. How is the organisation of family and collective solidarity adapting in this context of longer life spans, low fertility, and work that is simultaneously scarce and abundant?The welfare states are currently facing three main challenges: ensure satisfactory living conditions for the elderly without increasing the cost burden on the active population, reduce social inequality, and maintain equity between successive generations. In this book, researchers from different countries compare their experiences and offer contrasting views on the future of social protection. They consider the theoretical aspects of the intergenerational debate, relations between generations within the family, the living standards of elderly people, and the question of social time.