Relatively little is known about characteristics of sexual assault survivors who present to the emergency room. Examination of differences in survivor, assault, and exam characteristics by type of offender (intimate partner, acquaintance, acquaintance-just-met, and stranger) was conducted using intake data collected from 331 women who presented to an emergency room and were examined by a Sexual Assault Nurse Examiner between 2001 and 2004. First, the data suggest there is a difference in injury patterns depending on the survivor--offender relationship. Second, there was a high rate of women assaulted by a known offender presenting to the emergency room. Third, there are important differences in survivor substance use among women assaulted by different offenders. Implications for research and practice are discussed. (Contains 3 tables.)