"We examine whether women and men of the same ability differ in their decisions to seek challenges. In the laboratory, we create an environment in which we can measure a participants performance level (high or low), where a high performance level participant has on average higher earnings from solving a hard rather than an easy task, and vice versa. After we identify each participant's performance level, they choose the difficulty level (easy or hard) for the next two tasks (only one of which will be chosen for payment). Although there are no gender differences in performance, or beliefs about relative performance, men choose the hard task about 50 percent more frequently than women, independent of performance level. Gender differences in preferences for characteristics of the tasks cannot account for this gender gap. When we allow for a flexible choice high performing women choose the hard task significantly more often, at a rate now similar to the decision of men. Such a flexible choice makes challenging choices easier when participants are either risk averse, or uncertain about their ability. Our results highlight the role of institution design in affecting choices of women and men, and the resulting gender differences in representation in challenging tasks"--National Bureau of Economic Research web site.