Every other person in the world today lives in a city. Of these, one-third live in slums or sub-standard housing and are poor. How nations deal with this rapid pace of urban growth and the crisis of urban poverty is the subject of a meeting at the United Nations this week. A special session of the General Assembly from June 6 to 8 will bring together representatives from 171 countries who met five years ago in Istanbul, at what came to be known as the City Summit, to consider these issues.