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A new technique is pesented for measuring soil water tension, using the relation between the dielectric behaviour and the water tension of an absorbent placed in the soil. A practical realisation of the dielectric tensiometer is described, consisting of a porous metal cylinder as an outer conductor, containing an inner conductor, and filled with glass beads which serve as an absorbent. Together they form a coaxial condenser system. The electrical capacitance between the two electrodes is a measure for the soil water tension. The dielectric tensiometer is usable from zero to over 10 bar, without suffering from most of the common disadvantages of tensiometer pressure transducer systems. The dielectric tensiometer is ideally suited for use in conjunction with a capacitive soil water content meter for determining the water-retention characteristics of soil material. Patent is pending for the dielectric tensiometer.