Abstract
Parties vary substantially in the proportion of women they send to parliament. I examine how party characteristics affect women's representation in the parliamentary parties of 12 advanced industrial nations over time. Four party-level factors have some explanatory power: organizational structure, ideology, women party activists and gender-related candidate rules. A temporal sequence is proposed in which these factors and electoral rules directly and indirectly affect women's representation. Women party activists and gender-related rules are the more direct mechanisms affecting women's legislative representation. Further, New Left values and high levels of women activists within the party both enhance the likelihood that gender-related candidate rules will be implemented.