Female participation in engineering has never topped 20% nationally for the proportion of bachelor's degrees earned by women. Research on this topic, as well as related self-esteem literature, suggest that women may be more likely than men to leave engineering if they have unmet grade expectations. Additionally, the presence of more women in engineering courses may positively influence women's persistence through peer reinforcement and the mitigation of possible social identity threat. This study explored differing degree outcomes for four cohorts of baccalaureate men and women (N=3,087) in a selective undergraduate engineering program by examining persistence at three levels: within the institution, within engineering, and within the originally intended engineering major, using three nested logistic regressions with increasingly restrictive criteria. The study hypothesized positive relationships between women and grades, between women and the proportion of other women in engineering-related courses (female density), and a conditional relationship among being female, grades, and female density. Women with high grades and a higher female density in courses should be more likely to persist in their originally chosen major or within engineering than men in the same situation. The findings did not support these hypotheses. Grades influenced men and women equally at the institution and major levels. At the engineering level, however, men were more grade sensitive than women when earning equal GPAs after the first year in college. In terms of female density, the study found negative main effects at all three levels. Moreover, the negative interaction between being female and female density approached significance at the engineering level. A different statistical method is needed, however, before any conclusions can be reached. The study also finds a flow of students between engineering fields as well as out of engineering, with aspiration to some majors facilitating the former or the latter. The significant majors change with the level of analysis. Finally, if historically underrepresented students graduate within six years, they are more likely than majority peers to graduate in their originally intended major. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]