Attacks by strangers, as compared to attacks by acquaintances, were more likely to involve older victims and white victims; involve threats or weapons; occur outdoors; involve two or more attackers; and include penetration. Acquaintances were more likely to hit their victims and to hold them for a longer time; victims were more likely to resist when they knew their attackers. Finally, victims of stranger rapists were more likely to suffer injury. Multivariate analyses indicate that physical resistance was significantly related to injury and more strongly related to injury when the rapist was a stranger. 2 tables, 4 notes, and 25 references