An Indian woman coming of age in 1960 would have had, typically, six children, according to United Nations data. Today, Indian women have just over two children on average. It's a shift with profound implications, and one that doesn't fit most people's expectations. The U.N. Population Division predicts that 11.2 billion people will burden the Earth at the end of the century. If it happens, it would trigger an overpopulation crisis. But a growing number of demographers and other authorities are beginning to doubt those predictions. They believe the future will be defined not by a population bomb, but by a population bust. To research the planet's population future, we talked about family size with people on six continents - academics and statisticians and government officials, but also young women and men who agreed to sit down for a chat about their futures. In addition, Ipsos Public Affairs polled people in 26 countries - developed and developing - asking how many children they wanted. What we discovered is that almost everywhere women and men want about two children on average, a birth rate that will stabilize global population and may mean it will drop, rather than explode. Rapid urbanization appears to be what's driving the trend. Fifty-five percent of the people on the globe now live in cities. As people in developing companies leave the countryside, women gain access to media, to education, to information from other urbanized women, and they choose to have small families.