"4MAPS", a new parcel-level GIS protocol that supports sustainable communities, was adopted last year by the city of Mill Valley, CA as part of its new housing element. This protocol was presented to the National GeoSpatial Advisory Committee on April 2 and to the American Association of Geographers on April 14, in order to promote its use 4MAPS nationwide. The 4MAPS protocol reflects the federal government's "Six Livability Principles" by creating four parcel layers – DESTINATION, WALK, TRANSIT and SOLAR -- that score each parcel development potential in terms of its likelihood to minimize automobile usage. These maps can be used to direct new housing into those areas most suitable to result in smart growth. By using this protocol, local government is able to enable a large number of public and private entities to develop and redevelop housing into areas that will benefit the entire community.