The attached powerpoint slides outline four key challenges that arise from this trend. The first is simply the challenge of creating and maintaining the infrastructure necessary to manage urbanization. The rapid growth of cities, especially in developing countries, far outstrips the ability of national and local governments to create water and sewage systems, transportation facilities, and housing.

Second, rapid urbanization is creating problems of ecological management. Urbanization around the world consumes land at a rate greater than the growth of urban populations; i.e., our urban settlements are spreading at lower densities over ever greater land areas. Sprawling urbanization puts intense pressure on natural ecosystems, and thus creating sustainable patterns of urbanization is an important challenge we will be facing in the years to come. In addition, most of the world’s urban growth is taking place in coastal cities, 12 of the 15 mega cities in the world are coastal. If global climate change generates a rise in sea-level, hundreds of millions of urban dwellers are at risk.

Third, our urban areas must deal with rapidly increasing social and ethnic diversity. In the U.S., suburban areas now have more poverty than central cities, and they have more immigrants than do the central cities. Patterns of mobility and immigration are producing a bewildering array of social and ethnic groups sharing the same urban space. How we deal with that diversity will be very important. Can we build multicultural urban areas to take advantage of diversity and the economic and social benefits it can produce? Or are we lurching toward some dystopian future of segregated urban spaces in which economic deprivation or ethnic differences are overlaid with spatial segregation?

Fourth, we see significant challenges in urban governance on two levels. First, rapid advancements in information technology is producing a population with different expectations regarding urban planning and the roles of ‘amateur’ citizen and ‘technocratic’ planner in that process. Can we use IT to provide citizens with greater understandings of planning and policy outcomes? In addition, will we be able to match the scale of governance to the scale of our urban problems? In the U.S. at the turn of the century there were over 85,000 separate local governments in existence. But, our urban areas grow into regions with housing markets, labor markets, transportation systems, and watersheds and natural resource systems that span municipal boundaries, county lines, state lines, and sometimes international borders. To fully address our urbanization challenges in the future we need to devise governance systems that have the capacity to act across jurisdictional boundaries.

While these may seem like formidable challenges, and indeed they are, we sometimes forget how much our daily decisions influence outcomes. One urban planner estimates that in 2030, one-half of all buildings in the U.S. will have been built since 2000. And, remember the World Bank’s estimate that in 30 years cities in developing countries will create new urban space equal to what the entire world has settled to date. To me, those observations suggest that we are not simply being swept along by some unmanageable tide of events. On the contrary, our actions every day contribute to building the future of our urban areas.