A software tool has been developed to predict the SAR signatures created by buildings. The tool is an integration of a building model editor with a SAR signature simulation algorithm. The SAR signature simulator is capable of producing single and multiple bounce signatures from building model inputs. These signatures are computed in near real time and are displayed as colored graphic overlays superimposed over a gray scale SAR image. The building model editor is capable of creating and manipulating buildings with photogrammetric rigor in three dimensions. The result of the integration of these two components is a tool that rapidly predicts SAR signatures as an image analyst manually adjusts building models. Future work is also discussed.