Abstract: A moisture detection system (100) comprises a cable (102), a voltage regulator (104) and a differential amplifier (106). The cable (102) comprises an elongated non-conductive moisture permeable structure (108), a first elongated lead (110) and a second elongated lead (112). The first and second leads (110, 112) are substantially equal in length and are connected to the differential amplifier (106) and arranged such that they are not in galvanic contact with each other at any location along the cable (102). The voltage regulator (104) is configured to supply a regulated voltage to the first lead (110) and to the differential amplifier (106). The differential amplifier (106) is configured to determine a voltage difference between the first and second leads (110, 112), and configured to provide a signal that is representative of the determined voltage difference.