This paper presents our research and development effort towards a real-time 3-D situational awareness visualization for emergency response (3D-SAVER) in urban environments. For achieving the 3D-SAVER, key enabling technological components (including GIS image/data processing, 3-D building modeler, interactive visualization, and dynamic scene update) were developed and integrated. The resultant 3D-SAVER prototype is capable of not only automatically collecting and processing image & information (pertinent to the incident site) for generating complex building models, but also taking real-time positional measurements of people & resources within multi-story buildings and providing an interactive visualization of the integrated information to the incident commanders for 3-D situational awareness. The feasibility and efficiency of 3D-SAVER were demonstrated by a fire incident simulation using practical San Diego datasets. By enabling improved 3-D situational awareness, our 3D-SAVER holds the great potential to increase the speed and effectiveness of emergency response, thus saving lives and decreasing costs.