As the world population grows, cities are feeling the crunch. By 2030, nearly 5 billion people are expected to be living in "megacities" with populations over 10 million. To accommodate all these residents, cities around the world (including New York City) are adopting Sustainability Plans. But what makes a city "sustainable" - and can it be measured? The SustainLane 2006 US city rankings evaluates the 50 largest cities according to metrics like water- and air-quality, efficient use of resources, renewable energy, accessible and reliable public transportation, and green building practices. The authors also look for parks, greenbelts and access to locally-grown food. But how do these US cities compare to their foreign counterparts - to cities like Kalundborg in Denmark, a celebrated example of an industrial ecosystem, or to
Hammarby Sjöstad in Sweden, which was awarded the 2007 World Clean Energy Award? Building on the question of what makes a city sustainable, this panel will highlight best practice examples from around the world, and assess NYC's PlaNYC 2030 in comparison to them. In addition, since nearly half of greenhouse gas emissions come from buildings, we will explore the role of "green-building" in helping cities meet their sustainability goals.