Women legislators are more likely to serve on committees related to women’s issues and to sponsor women’s issues bills, but it is unclear if these patterns are driven by district preferences, differences in background, or institutional factors. We introduce new data on the legislative activities of over 25,000 U.S. state legislators to help explain these patterns. After accounting for district preferencesin a difference-in-differences design and for candidate backgrounds via campaignfundraising data, we find that women are still more likely to focus on women’s issues. They are also less likely to serve on top-flight committees, chair those committees, or serve in leadership. However, once a woman joins the leadership, women’s representation on top-flight committees appears to increase. Together, these results suggest that underlying structural features of the legislative environment are an important reason why men and women behave differently as lawmakers.