International and domestic high courts remain dominated by male judges. While an important literature examines variation in how judges of different genders decide cases, we know little about gender differences in the performance of judges. I argue that due to selection effects that arise because of discrimination in appointment processes, female judges are likely to outperform their male counterparts. I empirically assess this argument in the context of the European Court of Justice (ECJ). I show that female judges in the ECJ tend to issue more decisions than men and that they are more often selected to influential positions in Court. However, these findings pertain to non-salient cases, suggesting that the Court assigns women judges to do the "house work" and selects male judges to the most prestigious positions. I conclude by discussing whether my findings suggests that the Court, along with the appointing governments, reinforce a male dominated international bench. The implication of this is that even when women break the glass ceiling, they still face unfair biases and barriers.