The use of advanced embedded system technologies such as microelectromechanical system (MEMS) sensors and wireless communications hold great promise for measuring the response of civil structures to ambient and external disturbances. In this paper, the design of a high-performance, planar piezoresistive MEMS accelerometer is discussed in detail. The piezoresistive accelerometer possesses superior performance characteristics including low noise densities when measuring local structural responses characterized by high-frequency content. A low-cost wireless sensing unit, designed for automated structural monitoring, is utilized to record and wirelessly transmit measurements obtained by the piezoresistive accelerometer. To validate the performance of the wireless monitoring system including the interfaced piezoresistive accelerometer, a five degrees-of-freedom laboratory test structure is utilized.