SECURESTM (System for the Effective Control of Urban Environment Security) is being developed to support local law enforcement in the critical problem of gun-related violence on America's streets. Once deployed, SECURES will instantaneously detect, recognize, and pinpoint the location of gunfire, and transmit this finding to the police dispatcher or directly to scout cars in the vicinity. Local law enforcement and trauma care resourses will be able to respond quickly, thereby dramatically increasing the probability of arrest of the gunman and survival of the victim. SECURES will employ an air-acoustic detection grid composed of small, low-cost, battery powered sensor modules, called Pole Units. These modules will be located on utility poles and buildings primarily at city block intersections, and consists of an acoustic sensor, signal processing electronics, and a transmitter. Development efforts have concentrated on i) developing and testing algorithms capable of identifying gunshots with an extremely low false alarm rate, ii) developing ultra- low power electronics capable of reliable operation for long periods in outdoor environments, and iii) determining the RF communications design. Pole Unit prototype electronics and gunshot identification algorithms have been developed and successfully tested on an extensive database of recorded gunshots and background noises.