In the initial experiment, 20 male and 20 female heterogeneous stock (HS) mice were divided randomly into experimental and control groups. Ethanol was administered in liquid diet form to the experimental group in increasing dosages for a 9-day period followed by behavioral and physiological tests to determine differences between groups and genders 6 to 7 hr post-withdrawal. Analysis of data showed significant differences between the ethanol-treated and control groups for at least six of the measures. In addition, significant gender differences and significant interactions between gender ant treatment group were found for four of the measures; in all of these cases, females appeared to exhibit a less severe withdrawal syndrome than males. In a second experiment, no gender difference in rate of ethanol disappearance from the blood could be found in 36 HS mice tested at 1 to 3 hr post-withdrawal.