Although the Charter of Venice (1964) emphasized the need to preserve and reveal the aesthetic and historical value of historic buildings, a second duality has emerged between the historic value of a building and its value as the visual embodiment of that history. Describes a project in Bangor, Maine, where a different approach to the design guidelines for the preservation and rehabilitation of buildings in the city center had to be developed and implemented. Instead of limiting the project to a general set of guidelines, the design team developed a series of recommendations for each building and included a special section called items to preserve, in which unusual details were noted. These elements included a surviving original window sash, early paint colors, evidence of early changes to the building, significant period storefronts, and visually and historically important signs. Concludes with comments on the importance of public education in the preservation of historic architectural evidence.