ONE OF THE MORE RECENT AND COMMONLY USED SUSTAINABILITY METRICS is called eco-effi ciency . Developed in 1992 by the World Business Council on Sustainable Development (WBCSD) (2005a and 2005b, www.wbcsd.ch), it brings together the essential ingredients necessary for increased economic prosperitymore effi cient use of resources and lower emissions. This framework can be used by any business to measure progress toward economic and environmental sus tainability.