Since 1991 at least ninety countries have implemented some type of provision for increasing women's representation. Activists have assumed that quotas for women in legislatures would provide a critical mass of women who would then be empowered to shift policies toward a more women-friendly agenda. Such quotas, however, do not consistently result in increased numbers of women elected. Even in countries with significant women's representation, policy change is uneven. Studies show that the impact depends on many factors, including the electoral system, the origins of the impetus for quotas, the type of democracy, political and social culture, class structure, and the strength of the women's movement. This article will explore these many factors and how they reinforce or undercut efforts both to increase the numbers of elected women and to pass legislation that addresses gender equity.