We have studied couple conflict primarily through the peculiar window afforded by homicide. This research has been premised on the notions that homicides, although rare and obviously extreme, frequently represent the culmination of conflicts whose substance is not so rare, and that factors associated with variation in the risk of being killed by one’s partner are likely to be associated with variation in the prevalence and intensity of nonlethal couple conflict, too. If these premises are sound, then lethal violence holds two advantages as a conflict “assay”: high face validity as a reflection of genuine conflict, and relatively minor problems of biased detection or reportage. In this chapter, we review findings about the epidemiology of spousal homicide, and also discuss evidence bearing on the premise that patterned variation in the incidence of lethal violence parallels variations in the much more prevalent phenomena of “normal” violence and coercive control. A pervasive theme is the importance of male sexual proprietariness as a motivational factor in severe couple conflict.