Just as scientific technology has given us the miniature micro chip to reduce the physical size of computers, it has also given us that same technology to build miniature microphones, transmitters, and other eavesdropping devices.

Valuable information must be obtained from within sensitive areas for a covert operation to be successful. Numerous inherent weaknesses exist which could easily be exploited by an electronic eavesdropper.

Addressed are those weaknesses which are considered practical for eavesdropping attack. Technical surveillance methods are of four general categories:

Telephone Attacks
Hardwired Attacks
Radio Frequency Transmitter Attacks
Esoteric Attacks