20 Most Sustainable Cities

"Many (cities) are responding to the needs of their citizens (read: financial demands) by developing sustainability plans. Some of the plans are good; some aren't. The one thing they share is that they all have a target year in the near future when their sustainability makeover will be complete. For example, Abu Dhabi has 2030 as its target end goal, while Honolulu is looking 10 years down the road to 2018. By and large, however, most cities are focusing on the year 2020 and therefore that is the target date for becoming a 2020 Global Sustainability Center.

So which cities have the best plans? Throughout these pages, you'll be introduced to the 10 leading cities that we are calling "2020 Global Sustainability Centers," (as well as 10 mid-sized cities that deserve recognition). These Global Sustainability Centers-or GSCs for short-are all large, cosmopolitan, economically-significant cities. After all, it's much easier for a small town to become sustainable, but that doesn't solve the problems of the Hong Kongs, Los Angeleses and the Sáo Paulos of the world (or the approximately 37 million people that collectively live in these three cities alone).