Planned unit development
In the United States, a planned unit development (PUD) is a type of flexible zoning device that redefines the land uses allowed on a site, and also the resulting unitary site plan. PUDs group together both varied and compatible land uses—such as housing, recreation, commercial centers, and industrial parks—within one contained development or subdivision. They facilitate development flexibility and the combination of mixed-use development with environmental preservation and sustainability, including open space. Developed areas vary in size and by zoned uses, including industrial, commercial, and residential. The first use of a PUD is believed to have been in 1949. Comparable zoning devices include floating zones, overlay zones, special district zoning, performance-based codes, and transferable development rights.