THE INSTRUSION SENSOR OPERATES AT VHF FREQUENCIES AND IS DESIGNED TO PROTECT HIGH-VALUE INDIVIDUAL RESOURCES. THE SYSTEM CONSISTS OF A LOOP OF LEAKY COAXIAL CABLE THAT ACTS AS A DISTRIBUTED TRANSMITTING ANTENNA ENCIRCLING THE RESOURCE. ONE OR MORE STRATEGICALLY-LOCATED MONOPOLES ACT AS RECEIVING ELEMENTS. AN INTRUDER DISTURBS THE AMBIENT FIELD AS HE OR SHE CROSSES THE LEAKY CABLE SENSOR, THUS PRODUCING A DETECTABLE CHANGE IN THE RECEIVED SIGNAL LEVEL. COMPUTED AND MEASURED VALUES FOR VARIATIONS IN RECEIVED POWER IN THE PRESENCE OF AN INTRUDER SHOW GOOD AGREEMENT ACCORDING TO AN ANALYSIS OF A SINGLE-WIRE INDIVIDUAL RESOURCE PROTECTION SENSOR. THE SINGLE-WIRE INDIVIDUAL RESOURCE PROTECTION SENSOR IS VIEWED AS AN EFFECTIVE TECHNIQUE IN PROVIDING PHYSICAL SECURITY FOR HIGH-VALUE ISOLATED RESOURCES. A PHENOMENOLGICAL THEORY DESCRIBING THE PERFORMANCE OF THE SYSTEM IS PRESENTED. THE RESPONSE OF THE SYSTEM WHEN DEPLOYED AROUND A PARKED AIRCRAFT IS SHOWN, AS WELL AS SOME RESULTS OF A SWITCHING TECHNIQUE THAT REDUCES THE IMPACT OF CABLE ATTENUATION ON DETECTION SENSITIVITY. ILLUSTRATIONS AND REFERENCES ARE INCLUDED. (DEP)