Research findings of sex-symmetry in the perpetration of intimate partner assaults have sparked vigorous debate about the appropriate definition and measurement of intimate violence. A neglected but central issue in this debate is the conceptualization and measurement of gender. This article first examines the often unstated theoretical perspective on gender that underlies the research on sex-symmetry in intimate partner violence. This perspective treats gender as an individual characteristic of persons. Next, I describe challenges to the individualist model of gender from two emerging theoretical perspectives—interactionist and structuralist gender theories. The article concludes with suggestions for research on intimate partner violence that are informed by these new gender theories.