Throughout human history, the old have subsidised the young. In rich countries, however, that flow has recently started to reverse. Ronald Lee of the University of California, Berkeley, and Andrew Mason at the University of Hawaii measured how much people earn at different ages in 23 countries, and how much they consume. Within families, intergenerational transfers still flow almost entirely from older to younger. However, in rich countries public spending favours pensions and health care for the old over education for the young. Much of this is paid for by borrowing, and the bill will one day land on the young. In five of 23 countries in Messrs Lee and Mason’s sample (Germany, Austria, Japan, Slovenia and Hungary), the net flow of resources (public plus private) is now heading from young to old, who tend to be richer. As societies age, many more will join them.