The number of deaths of children under the age of five declined from 12.4 million in 1990 to 8.1 million in 2009, which means nearly 12,000 fewer children die each day. Some of the world’s poorest countries have also made impressive gains in the fight against poverty, but the least developed countries still lag in efforts to improve living standards.

Nothing short of a technological revolution on the scale of the first industrial revolution will be required to meet the challenge of sustainable development. Enormous improvements in human welfare have taken place over the past two centuries, but at a lasting cost of degradation of our natural environment. Continuation along established economic growth paths means that the Earth's capacity to ensure human welfare and serve as a sink for the waste and pollution generated in the creation of that welfare will be exceeded.

The World Economic and Social Survey 2011 analyses the challenges and options involved in shifting to a "green economy" based on more efficient and renewable…