This article is an appeal for independent, broad architectural-historical research prior to the redevelopment of buildings to protect their potential historical value and cultural significance. Authenticity is understood here as historicity and the article explores what it might signify in adaptive reuse, a growing sector in architectural design that is increasingly coming to be regarded as a separate discipline. In strategies of adaptive reuse the building is viewed primarily as an architectural object that is to be given a ‘new life’. But does that allow sufficient attention to be paid to the historicity of our living environment? How resilient and sustainable is a repurposed building? Stories that touch on the building, on testimonies in which place plays a role, on the intentions behind the design, and on changes to use: all these intangible aspects together determine the cultural value of the building in society, community and setting. That historicity, or genuineness and singularity, is crucial to the building’s significance. What is needed above all is for the description of the historical and accumulated cultural value and significance of a building and place to be the starting point for redevelopment. Otherwise the spirit of the place disappears to be replaced only by novelty and entertainment, at the service of the contemporary consumer.