This background paper is intended to support Member states in strengthening multidisciplinary and coordinated crime prevention and criminal justice responses to gender-based violence and gender-related killing of women and girls. This includes in-depth review of cases, and exploration of the possibility of establishing domestic homicide and violent death review committees. The paper presents and compares the main characteristics of two key initiatives focused on learning from gender-related killing (also referred to as "femicide" or feminicide") to improve responses: the use of death review committees in domestic violence cases and Femicide/Feminicide Observatories. The paper was prepared under UNODC’s mandate to support national efforts to eliminate violence against women and action against gender-related killing of women and girls, under General Assembly resolutions 65/228, 68/191 and 70/176.