The present study was designed to examine factors that could facilitate or impede adherence to proper hydration. Forty volunteers (20 male, 20 female) were randomly assigned to one of two groups: Informed Group (n = 20) and Uninformed Group (n = 20). Bioelectrical impedance was used to measure intracellular (ICW) and extracellular (ECW) body water at Time 1 and 2. Personality, health beliefs, and health behaviors inventories were administered at Time 1. A health information brochure on proper hydration and consequences of poor hydration was given to the Informed Group. All participants were given six 1-liter bottles of water and drank two bottles per day. Both ICW, F(1,38) = 4.79, p < .05, and ECW, F(1,38) = 10.12, p < .005, significantly increased for both groups, and females had significantly greater changes than males in ECW, F(1,38) = 4.43, p < .05, and ICW, F(1,38) = 4.48, p < .05. Health information had no significant effect on female adherence but was a significant predictor of male adherence,  = .266, p < .05. Agreeableness, r = .36, p < .05, and social desirability, r = .33, p < .05, were the only personality factors related to change in ECW for the group as a whole. Health beliefs were unrelated to adherence, but general health concern,  = –.–.053, p < .05, was a significant predictor of change in ECW for males, although it was an inverse relationship.