Gender stereotypes are understood as the ascription of different personality traits to men and women. Data from American and Italian samples showed that consistent with the attribution hypothesis, the estimated prevalence of a trait in a target group predicted perceptions of trait typicality well. In contrast, there was no support for the categorization hypothesis, according to which perceived differences in trait prevalence between groups should independently predict trait typicality. Nevertheless, participants overestimated gender differences in personality as predicted by the principle of intercategory accentuation. The implications of these findings for the rationality and accuracy of gender stereotyping are discussed.