Understanding femicide or “gender-based killing of women” 1 depends, to a large extent, on the existence of data deriving from detailed and reliable records that identify characteristics of the victim, the perpetrator, the relationship between the two, their environment, motivations and patterns of behaviour, among other factors. The Gender Equality Observatory for Latin America and the Caribbean has made progress in measuring femicide in the region and has gathered reliable, verifiable and comparable information from the countries, with a view to using it to design, implement and evaluate public policies on protection for victims of violence, prevention of femicide, reparation for dependent collateral victims, and punishment of perpetrators.