See architect and activist Edward Mazria's compelling presentation, which calls on buildings to be carbon neutral by the year 2030. Mazria has been speaking to leaders from the building industry and government on practical ways to reduce buildings' carbon footprint.

"e²: the economies of being environmentally conscious" is an ongoing PBS documentary series about solutions to the world's most pervasive environmental challenges. The 2007 season continues with "e² design season two", the flagship sustainable architecture series examining innovations in green building and planning from around the globe. Check your local PBS listings for television broadcast dates in your area.

The "e²" series and its video podcasts are produced by kontentreal, and distributed within the United States by PBS. More information is available at pbs.org/e2/ and e2-series.com/