Introduction       Mam Suteethorn, Jean Wu       LEED (LEADERSHIP IN ENERGY&ENVIRONMENTAL DESIGN) The U.S. Green Building Council       Sustainability has clearly become an important factor in architecture and landscape architecture. What is less clear are the questions of what does sustainability mean and what standards qualify constituting sustainability. LEED provides a standard to evaluate sustainability and environmental performance, and provides a basis of standards and vocabulary for people of different disciplines to work together.