Murder-suicide is a relatively rare event, and familicide is rarer still. However, it is certainly not unknown, and has been described in the scientific literature from both a socio-criminological and pathological-forensic perspective since the last century. In a civilized urban area such as Milan and province, where there is a general reduction in the homicide rate, homicide-suicide occurs almost exclusively within the family, and has specific features that differentiate it from other types of homicide, whether connected with general criminality or organized crime. This article analyses the quantitative and qualitative features of cases of homicide-suicide occurring in Milan and province between 1990 and 2009 (20 years), considering temporal aspects and the development of the events, the weapons used, and the epidemiological and psychopathological features of the perpetrators and their victims.