In this article, we investigate whether and how political parties function as gate-keepers in determining gender differentiations in committee appointments by using the Italian parliamentary committee system from 1994 to 2013 as a case study. Committee membership provides individual MPs with direct influence in a specific policy area as well as with visibility and expertise, thus affecting MPs’ political careers. Accordingly, to study women's appointments to committees’ positions is eventually to say something about women's chances to have an actual effect in the political process. After presenting the theoretical framework, three hypotheses are proposed. Our findings show that women tend to be appointed to committees dealing with stereotypically ‘feminine’ and ‘less prestigious’ issues, and that left-wing parties reproduce this pattern less than right-wing parties, but not when it comes to the appointment to more prestigious and influential positions. Moreover, we found that no significant longitudinal trends towards more unbiased distributions can be detected. A discussion closes the article.