In this paper, we investigate the impact of gender quotas on firm performance and corporate decisions using Belgium, France and Italy as a natural experiment. Our statistical analysis shows that the percentage of female directors significantly increases, and board members characteristics significantly change after the implementation of the gender quota. The results of our empirical analysis show evidence that gender quotas do not have a significant impact on both firm outcomes and corporate decisions. Our findings support the decision of policy-makers to use mandatory rules to force firm to achieve gender balance on corporate boards. Our results suggest that policy-makers create unrealistic expectations for women to boost firm performance, at least in the short-run when negative side effects of mandatory rules are potentially strongest.