Some police departments are already augmenting police patrols with listening devices and cameras. These pilot programs are drawing attention from police leaders in urban areas and from the American Civil Liberties Union, and the debate centers around the right of privacy. Although microphones and cameras have been in use in some European and Asian countries for several years, civil liberties groups and citizens in the United States have objected because they feel privacy is too large a price to pay for the new form of protection. An example of technology development is the Urban Gunshot Location System which triangulates the location of gunfire using microphones located on utility poles and rooftops over roughly a 1-square-mile area. Because the speed of sound is relatively constant, each microphone receives a sound at a different time and the input is relayed to the police department over telephone lines. A computer then mathematically triangulates the location of gunshots and displays them as a red dot on a digital copy of the city fire map. Acoustic sensor technology is being investigated by the Department of Defense and the National Institute of Justice. Cameras are being used to fight crime in Baltimore, Maryland, and in Hartford, Connecticut. Additional research is recommended to determine how video and audio technology in public areas affects crime. 4 photographs and 1 figure