Earlier studies have explored the differences between known-assailant sexual assaults and stranger assaults and reported the stranger assaults as being more violent. Only a few studies have discriminated between sexual assaults by intimate partners from assaults by other known assailants when comparing with assaults by strangers. In this study, we explored differences in the extent of violence and physical injury in sexual assaults committed by intimate partners compared with assaults by strangers and acquaintances. Medical and forensic records of 690 consecutive women attending a sexual assault center in Stockholm, Sweden were reviewed. The final sample included in the analysis consisted of 503 patients. Our results showed that women sexually assaulted by their intimate partners more frequently reported physical violence (OR = 4.1) than women assaulted by strangers (OR = 2.0) and acquaintances (OR = 1.0). Genital injuries were not found to be related to the victim-assailant relationship in this study. Extragenital injuries showed a tendency toward being more frequently found after intimate partner assaults compared with stranger and acquaintance assaults; however, this was not found to be significant in adjusted analyses. Previous history of sexual assault was more common, and seeking medical care within 72 hr as well as being under the influence of alcohol during the assault was less frequent among intimate partner victims. These results support the conclusion that sexual assaults committed by intimate partners, contradictory to earlier studies, are likely to involve more physical violence and result in injuries just as often as assaults committed by strangers. (Contains 4 tables and 1 figure.)