The relationship between degree of water deprivation and affective value of a.2% sodium saccharin solution was determined for 15 female albino rats in a one-bottle test situation. Initially, ad lib animals greatly preferred saccharin, whereas rats deprived for 231/2 h decreased their fluid intake and the 47-h deprived showed no initial change. Subsequently, these effects did not appear when a 1% sodium chloride solution was presented to assess effects of stimulus change. Thus, the effect observed with saccharin may not be simply due to novelty of the new solution.