Findings are reported from a survey examining the frequency with which women in currently aggressive same-sex relationships also report aggressive past relationships involving female partners, male partners, or members of their family of origin. Particular attention is paid to victims who also used aggression and their perceptions of whether their aggressive behavior was self-defensive or mutually aggressive. Results indicate that about one-fourth of participants had been victims of aggression in current relationships, roughly two-thirds had been victimized by a previous male partner, and almost three-fourths had experienced aggression by a previous female partner. Among those reporting having been both victims and users of aggression, about one-fifth had used aggression in their current relationship, almost one-third used aggression with a previous male partner, and nearly two-thirds had used aggression with a previous female partner. A majority of victims who had also used aggression with a previous male partner characterized this use as self-defense, as compared to only 30% of those who had used aggression with a female partner. Instead, aggression in relationships involving a female partner was most frequently described as mutually aggressive in nature.