The reason that girls and women withdraw from science and technology education and careers has been a universal concern in the social sciences. This study investigated how gendered constructions of identity are translated into the barriers and fears that female students and professional women experience in decision-making about their careers. We conducted interviews with 63 girls and 39 women in academic and professional engineering careers, focusing on their interpersonal relationships with boys and men in their school and occupational engineering settings, respectively. Participant discourse highlighted the difficulties women face when managing the antagonistic discourses of femininity and masculinity in a social environment in which they are frequently forced to submit to hegemonic masculinity. The consequences of women's differing discourses about the "masculine world" and the "feminine world" are discussed, and some strategies for creating more equalitarian relational environments in school and work settings are discussed.