Book excerpt: Gender-based violence against women remains one of the most pervasive human rights violations of our time and affects women disproportionately because of the unequal distribution of power between women and men and the structures supporting this imbalance, which deprives women of enjoying fundamental freedoms. Combating gender-based violence is a declared goal of the EU institutions and all EU Member States. The overall objective of this study on Administrative Data Sources is to extend the knowledge about the situation of, and possibilities for, administrative data collection on gender-based violence in the EU-28 Member States, and to gain a comparable overview of the extent, nature and consequences of gender-based violence across the EU-28. Administrative data reflect only what is recorded by an agency interacting with a victim or perpetrator of gender-based violence and never the prevalence of gender-based violence due to the high rate of unreported incidents.^But administrative data can provide detailed information on how police, judicial, health and social services respond to the prevention, protection and prosecution of gender-based violence. The availability of this data in all Member States makes administrative data providers a valuable source of information to be assessed. The results and main findings of the study have been divided into two different reports. The first part is focused on the legal framework and regulations underpinning administrative data collection on gender-based violence at international and national levels. The second report (current one) describes and analyses the current situation and potential of administrative data sources and related statistical products identified through this research.^Both reports seek to support policy-makers across Europe in the struggle against gender-based violence by providing guidelines and suggesting methodological tools and indicators to improve and make comparable administrative data collection on gender-based violence in the European Union.