Global life expectancy now stands at 71 years compared with 30 years in 1870. This fact increases the need to understand how we age and how that impacts our economic decision making. It also raises the issue of how we should change our life cycle behaviours, policies and institutions to adapt to these longer lives. The combination of these two factors leads to a very different focus from the traditional interest of an ageing society and its focus on changes in the age distribution of society.