Despite having the raw ability to pursue careers in science and engineering, gifted girls often shy away from such careers. Here, the authors explore two explanations for this puzzling phenomenon. Specifically, they argue that exposure to (a) negative stereotypes about women's intellectual abilities and (b) stereotypes about scientists as "nerdy," eccentric loners may undermine gifted girls' confidence in their ability to succeed in science and engineering, their sense of belonging in these fields, and--ultimately--their interest. The authors also suggest evidence-based strategies for inoculating girls against these stereotypes and boosting their interest in science and engineering.