The preservation of open space has captured the public's imagination. Taxpayers are lining up to vote in favor of referenda authorizing their local or state governments to borrow funds to purchase open land or its development rights. Environmental groups are forming coalitions to support public acquisition of open space and the adoption of laws regulating development in and around open lands. Opponents of urban sprawl target the loss of open space as one of the major impacts of runaway development. The loss of open space is associated with the general degradation of the quality of community life. What is happening to open space is what is happening to the local environment, in the broadest sense of the word.

"Open space" is not easily defined. It includes parks, ball fields, pastures and meadows, scenic vistas, and fragile environmental areas, such as wetlands, ridgelines, and habitats. Some open lands—farms or fisheries, for example—are working spaces. Others are critical to the community's environment, while still others are simply undeveloped. One town defines open space legislatively as "land left in its natural state for conservation purposes or devoted to recreation or used for the preservation of distinctive, architectural, historic, geologic and botanical sites."