This paper documents the pervasiveness of women's lack of income security in old age across a large number of countries, but also points to a number of important policy measures that can be taken to address gender pension gaps. It focuses on how pension systems interact with other social and labour market conditions over women's life courses to increase or decrease gender inequalities in old age. It reviews pension systems to pinpoint the key sources of gender inequality in they way they are structured. The paper shows that crucial policy choices for the protection of women must take into account the conditions for entitlements in pension systems, the types of transfers that are promoted between women and men, the policy tools available to offset gender differences in paid work, earnings and unpaid work and the protection of the most vulnerable social groups through redistributive benefits. The paper concludes with some recommendations to make pension systems more gender equitable and suggests that policies aimed at achieving gender equality in pension rights and benefits need to work on several complementary fronts (including measures regarding pension system design, but also labour market regulation and the reconciliation of work and family life) and consider the diversity of women's situation across social strata as well as across countries. This paper was produced for UN Women's flagship report Progress of the World's Women 2015-2016
to be released as part of the UN Women discussion paper series.