Equality between women and men is a fundamental value of the European Union, enshrined in its Treaties and in the Charter of Fundamental Rights of the European Union. The EU plays a crucial role in ensuring that the principle of gender equality filters down from the international and EU level to national, regional and local levels. Over time and in various areas specific policies have been developed to improve gender equality in the European Union and in the Member States. To evaluate the level of gender equality in specific domains and on international or national levels different monitoring tools have been developed worldwide. However, an effective tool that measures various aspects of gender equality within the policy framework of the European Union was missing and became indispensable.