This sustainable element is grounded in the concept that increasing density on suitable portions of a site allows for preservation of the rest. Many sustainable site LEED credits for new construction reflect siting decisions related to the density of development such as walkable streets, bicycle paths; conservation of open space, proximity of mission related activities to housing and base services.

The redevelopment of brownfields is an even more challenging element of many sustainable development plans. Brownfields are abandoned or underutilized parcels of land that contain, or are suspected to contain, some level of contamination. Traditionally, brownfield sites have been thought of as suitable only for light commercial or industrial redevelopment, but increasingly reevaluations are being done which suggest that many sites could be appropriate for a multitude of uses, including housing and office space wildlife habitat, parks, open space and recreation.