Under certain conditions, women are more likely than men to vote for women candidates, a phenomenon referred to as a “gender affinity effect.” Causal mechanisms connecting women voters to women candidates are gender consciousness, desire for descriptive representation, support for liberal social policy, the use of gender as a shortcut to vote choice among low-information voters, and a “party-sex overlap.” Existing work is focused on American elections, which tend to be candidate centered, so little is known about gender affinity effects between voters and candidates in other contexts. This article focuses on Westminster-style parliamentary systems, using the Canadian federal elections of 2000 and 2004 as test cases. Women in these systems have the same motivations to gravitate toward women candidates, for they are gender conscious and desire descriptive representation. But they do not have the same incentives to cast ballots for women because political institutions and practices tend to discourage candidate-based voting. The article pays particular attention to a segment of the electorate we call “flexible” voters, which is comprised of independents, leaners, and defectors. In Westminster systems, it is this group of voters who should be most sensitive to candidate-based considerations.