Population seven billion: Growing numbers in Zambia
By the end of October 2011 the United Nations will announce that the world's population has reached seven billion.
The number of people on the planet is now rising by around 80 million a year.
But how are these changes affecting people's daily lives? BBC News speaks to seven people from around the world to hear their stories.
In Zambia, the UN predicts that the population could triple by 2050, reaching 100 million by the end of the century.
There is concern that this rapidly rising population will hamper economic growth and condemn future generations to poverty.
The BBC's Fergus Walsh went to a village just outside Lusaka to visit Catherine and Robert Phiri, who have just had a baby girl.