It is the process of making possible a compatible use for a property through repair, alterations, and additions while preserving those portions or features which convey its historical, cultural, architectural, structural, or functional values.

There are four approaches for the treatment of historic or contemporary properties: preservation (places a high premium on the retention of all historic fabric through conservation, maintenance, and repair). rehabilitation (emphasizes the retention and repair of historic materials, but more latitude is provided for replacement because it is assumed the property is more deteriorated prior to work), restoration (focuses on the retention of materials from the most significant time in a property’s history, while permitting the removal of materials from other periods), reconstruction (establishes limited opportunities to re-create a non-surviving site, landscape, building, structure, or object in all new materials).

Work involves property condition assessment, property rehabilitation report, detailed illustrations, method of statement, and construction supervision.