International migrants have an impact on their adopted society out of proportion to their actual numbers. The urban future carries many risks for the physical environment and natural resources, for social cohesion and for individual rights but it also offers vast opportunities. The experience of large cities as concentrations of human creativity and the highest forms of social organization suggests that the future will open new avenues for human development. Cities provide capital, labour and markets for entrepreneurs and innovators at all levels of economic activity. Cities already account for 60 to 80 per cent of the gross national product of many developing countries.
Cities also speed social transformation.
Indicators of health, literacy and social mobility are all higher in urban areas. Among these the key indicators of movement towards the equality and autonomy of women, such as closing the gender gap in education, access to reproductive health services including family planning and sexual health, and fairly-paid waged employment are also higher. The challenge of the urban future will be to sustain progress in social development in the face of unprecedented pressure. The assumption that urban growth will power development has held in many countries in Asia and some in Latin America. But even as urban-based economies grow, they are in danger of being overwhelmed by the sheer numbers of the poor and the dispossessed.