Gender equality is a matter of rights and fairness. As a fundamental value of the European Union, it is enshrined in its Treaties, including the Charter of Fundamental Rights of the European Union and going back to the 1957 Treaty of Rome. It is concerned with ensuring that all individuals have the possibility to realise their full potential regardless of their sex and/or gender. It does not solely focus on equality of outcomes, but extends to equal dignity and integrity. Evidence also suggests that gender equality plays a significant role in enhancing economic and social growth (Loko and Diouf, 2009; Duflo, 2012). The strong positive correlation between the Gender Equality Index and the gross domestic product across EU Member States ? as outlined in the first Gender Equality Index report ? is only one example of this relationship (EIGE, 2013). To reach the objectives set by the EU in the Europe 2020 growth strategy, gender equality has to occupy a central place within political debates in Europe. Measuring gender equality is an integral part of effective policymaking and supports the assessment of the outcomes of policy measures on women and men. Suitable statistics, data and measures are essential components of evidence-based policymaking and successful gender mainstreaming. Gender mainstreaming is not a goal in itself but a strategy to achieve equality between women and men. It is used to integrate gender concerns into all policies and programmes of the European Union institutions and Member States, as opposed to relying solely on measures specifically targeting gender equality. The Gender Equality Index can therefore contribute to the recommended systematic approach to the gender mainstreaming strategy advocated by the Employment, Social Policy, Health and Consumer Affairs Council (EPSCO) as an indicator to measure progress in gender equality (Council of the European Union, 2009a).