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A laboratory-scale experimental program was conducted which clearly indicated the feasibility of membrane electrodialysis for recovering potable water from urine. Since electrodialysis removes electrolytes from urine, pretreatment techniques were investigated for the removal of nonelectrolytes. These techniques were: charcoal adsorption, chemical oxidation, and enzymatic hydrolysis of urea to amnonium carbonate. A model of a urine reclamation system was built, comprised of two main processes: charcoal adsorption and electrodialysis. The system weighs 15 pounds, is less than one ft3 in size, and has a peak power requirement of 45 watts for 8 hours operation for the daily recovery of 3000 ml of potable water from urine. The daily energy requirement is 310 watt-hrs, including 160 watt-hrs for charcoal regeneration. Excellent quality water is recovered in yields of 92 %. The model has good relia-bility and can be readily adapted for condi4ns of weightlessness. _