In the frame of a Nationally funded research project, Satways Ltd. developed the G-Sense system, a low cost building rapid damage assessment system, comprising of a network of sensor nodes installed in different floors of a building measuring continuously building motion and more specifically, acceleration. The nodes include a low noise MEMS tri-axial accelerometer, a 16bit ADC, a power control (UPS) unit, an integrated processing unit enabling on-board processing, GPS for time synchronization and a gateway (mini PC) for real-time data acquisition, analysis and archiving. The gateway is calculating damage probabilities for every floor following an earthquake event based on the continuous calculation of inter-story drift ratio for every pair of sensors installed in consecutive floors and considering the fragility curve of every specific building. The damage probabilities are formulated as damage alerts and are sent to a central command and control software that monitors all G-sense installations in different buildings and visualize in a GIS system all received damage alerts. The central command and control software monitors also the nodes state of health and enables the change of the nodes and gateway configuration remotely when required. After extensive lab tests, the G-sense system was installed initially in several buildings for field testing in real conditions.