The cathodic response of the lead dioxide electrode to polyphosphate species examined. Fabrication and response of various forms of the electrode were investigated. Maximum sensitivity is obtained with an electroplated electrode, but overall convenience and utility indicate the paraffin wax-bound electrode as the device of choice. Scanning electron microscopy showed that the electrode surface consists of approximately 0.001 mm particles protruding from the paraffin 'floor'. Measurements of various polyphosphate solutions are reported. In addition, the measurement system was successfully applied to hydrolysis rate and metal complex stability evaluations. The electrode reaction provides a new and useful analytical tool for polyphosphate concentrations in water chemistry and water monitoring. The fact that the new method is specific for polyphosphates in the presence of orthophosphate suggests that it should be applicable to many water investigations.