Within the context of a Comprehensive Plan for the Town of Concord, as adopted in December 1990 by the Concord Town Planning Board and subject to amendment from time to time, the purpose of planned unit development regulations is to assist in the implementation of said Comprehensive Plan by providing a zoning technique to encourage flexibility in the design and development of land in certain specified zoning districts of this chapter in order to promote its most appropriate use; to facilitate the adequate and economical provision of streets, utilities and public spaces; and to preserve the natural and scenic qualities of open areas. Planned unit development (or "PUD") is a procedure intended to permit diversification in the location of structures and improve circulation facilities and other site qualities while ensuring adequate standards relating to public health, safety and welfare and convenience both in the use and occupancy of buildings and facilities in planned groups.