A Trial Comparing Interpersonal Therapy to Exposure Therapy for PTSD Due to Military Sexual Trauma (MST) in Male and Female Military Personnel

Inclusion Criteria: * English-speaking * Military Sexual Trauma (MST) survivors, with MST defined as actual or threatened sexual violence, from Vietnam era to current Operation Iraqi Freedom/Operation Enduring Freedom/Operation New Dawn * Diagnosed with PTSD consequent to MST, with a minimum CAPS score \> 40 * Medically stable at time of study enrollment (for persons with chronic injuries and that any disability present does not prevent attendance of weekly outpatient therapy sessions) * Ability to provide informed consent and function at an intellectual level sufficient to allow accurate completion of all assessment instruments * Stable on psychotropic medication for the prior 60 days Exclusion Criteria: * Lifetime or current diagnosis of schizophrenia or other psychotic disorder, bipolar disorder * Participation in a clinical trial or concurrent evidence-based treatment for MST-related psychiatric conditions or PTSD during the previous 3 months * Current evidence of significant unstable medical illness or organic brain impairment such that the patient could not attend sessions regularly or complete assessments * Patients who in the investigator's judgment pose a current homicidal or suicidal risk * Current or history of substance dependence in the past 90 days.