A preliminary procedure to assess rapidly the likely seismic performance of existing reinforced concrete buildings is presented. In this procedure, a Capacity Index is computed considering the orientation, size and material properties of the components comprising the lateral load resisting structural system. This index is then modified by several coefficients that reflect the quality of workmanship and materials, and architectural features. The procedure has been tested and calibrated based on the data compiled from damage surveys conducted after the earthquakes that occurred within the last decade in Turkey. The method classifies the buildings either as safe, meaning the building might suffer no severe damage or as unsafe, indicating that life safety performance level would not be met. (C) 2004 Elsevier Ltd. All rights reserved.