In the most general case, starting with two photographs of an architectural element, one forms a model of that element by analog or analytic methods and records that model either graphically or digitally. The procedure leads in all cases to a survey of the actual form of the building at the instant it was photographed. In addition if, by its nature, the photography is global and records the whole architectural surface, the photogrammetric plotting (passage from photographs to survey documents) can be selective. Thus characterized, photogrammetric metrology can be applied to surveys of the geometry and the analysis of abnormalities. For pathology, photogrammetric metrology can be used for deformation measurements, considered as absolute or relative values, and for following deformation changes. Likewise for cracks, photogrammetry can be used for making inventories and, under certain conditions, can provide considerable aid for their measurement and the follow-up of their evolution. In these applications, aerial photogrammetry at low altitudes has only rarely been used for superstructures up to now.