Although women have matched or surpassed men in many educational outcomes such as college access and persistence, female students remain much less likely to major in quantitative, technical, and science-related ﬁelds. While women have made progress in recent years, only 20 percent of engineering students are female, and the proportion of women receiving degrees in the sciences and engineering in the United States lags that of other industrialized countries (National Center for Education Statistics, 1995). This underrepresentation of women may have serious implications for women’s returns to education and may relate to occupational segregation and earnings inequality by gender (Linda Loury, 1997). As the economy shifts to favor these more male-dominated ﬁelds, there is concern that women will not be prepared to succeed. Moreover, the health of the economy depends on the production of certain kinds of degrees, and the underrepresentation of women in certain areas may contribute to shortages in critical ﬁelds.