USGBC - LEED

"LEED is a self-assessing system designed for rating new and existing commercial, institutional, and high-rise residential buildings. It evaluates environmental performance from a "whole building" perspective over a building's life cycle, providing a definitive standard for what constitutes a green building. The new LEED-Existing Buildings rating system addresses building operations and maintenance as well as systems upgrades in existing buildings."

- (Source: US Green Building Council website: www.usgbc.org)