It is fitting that a volume on post-traumatic stress includes chapters on sexual assault given both the prevalence of sexual assault and its effects. Specifically, in terms of prevalence, approximately one woman in five in the United States will be raped in her lifetime (Koss, 1993).1 In terms of the effects of sexual assault, victims experience heightened fear, anxiety, and depression for several months, and sometimes years, following an assault (see Frazier & Borgida, 1997, and Resick, 1993, for reviews). Sexual victimization affects physical health as well and is a more powerful predictor of physician visits and outpatient medical costs than other factors (e.g., age, smoking, alcohol use) known to be related to health problems (Koss, Koss, & Woodruff, 1991). Finally, sexual assault is one of the traumatic events that is most likely to lead to posttraumatic stress disorder (PTSD) (Breslau, Davis, Andreski, & Peterson, 1991; Norris, 1992; Ullman & Siegel, 1994). In a recent national study of trauma exposure and PTSD by Kessler and his colleagues (Kessler, Sonnega, Bromet, Hughes, & Nelson, 1995), almost half of the women who said that a rape was their worst trauma met lifetime criteria for PTSD. This is in comparison, for example, with a PTSD prevalence rate of 5% for those whose worst event was a natural disaster.