LEADERSHIP IN ENERGY AND ENVIRONMENTAL DESIGN (LEED) is a voluntary sustainable building standard that was launched by the US GREEN BUILDING COUNCIL (US-GBC) in the US in 1998. In the years since, LEED has grown from one standard for new construction to a comprehensive system of interrelated standards covering aspects from the design and construction to the maintenance and operation of buildings. It is also flexible enough to apply to all building types including both commercial and residential. Adoption of LEED is greatest in the US with over 30,000 buildings having been certified and many federal agencies, states, and local governments require or reward LEED certification. The standard has also been adopted in many countries around the world with over 6000 buildings certified abroad. Take up of the standard in the UK has been limited with only certified building to date, likely due to the prominence of BREEAM in the UK.