IMPORTANCE Many Vietnam-era women veterans served in or near war zones and may have experienced stressful or traumatic events during their service. Although posttraumatic stress disorder (PTSD) is well studied among men who served in Vietnam, no major epidemiologic investigation of PTSD among women has been performed. OBJECTIVES To assess (1) the onset and prevalence of lifetime and current PTSD for women who served during the Vietnam era, stratified by wartime location (Vietnam, near Vietnam, or the United States), and (2) the extent to which wartime location was associated with PTSD, with adjustment for demographics, service characteristics, and wartime exposures.