Studying “sex differences” in cognition is not a neutral activity, any more than studying “racial differences” in cognition (Caplan & Caplan 1997, 1999). As long as our society is sexist, racist, or biased in any other way, any claim to find group differences is likely, sooner or later, to be held up as proof of the more powerful group's superiority (Eccles & Jacobs, 1986; Wine, Moses, & Smye, 1980; Wine, Smye, & Moses, 1980). One illustration of the lack of neutrality of the study of sex differences is the title of this book, which suggests that its contents will be about the nature and extent of sex differences in mathematics. Indeed, several researchers have suggested that the very presence and the volume of studies of sex differences give the impression that differences have been found (this debate is reviewed by Favreau, 1997). Notice that in the wording of the title, Gender Differences in Mathematics, there is no implication that there is any question about whether there are such differences. However, the field has usually been referred to as “sex differences” rather than “gender differences” research, but in contrast, the use of “gender” in the title of this book serves the important function of suggesting the possibility that, whenever sex differences are found, they may be due to socialization factors rather than to the “biological” ones usually taken to be implied by the term “sex differences.