Gender quota do not always go hand in hand with a considerable rise in the number of women elected. Although the number of fe/male representatives elected depends on several factors, we argue that the stipulations of gender quota acts influence to a large extent their impact on the sex ratios in politics. This is not so much due to the share of fe/male candidates parties have to present than to the extent to which a gender quota act anticipates the particularities of the electoral system. A comparative analysis of three prominent cases, the Argentinean, Belgian and French gender quota acts, shows that the more a gender quota rule targets at the specificities of the electoral system in order to promote a gender balance in political representation, the more this rule 'guarantees' a result, even though gender quota acts concern but the input side of the electoral process.