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Dissociative electron attachment (DEA) to water in the gaseous phase has been studied using two different crossed electron–molecule beam apparatus. Ion yields for the formation of the three fragments H−, O− and OH− were measured as a function of the incident electron energy. The kinetic energies of the fragment ions were measured and compared with the values derived from ab initio calculations to provide information on the energy partitioning in the fragmentation process. Isotope and temperature effects on the attachment process are discussed and the production of OH− via DEA is confirmed.