In response to concerns of women veterans regarding the long-term health effects of military service in Vietnam, the Department of Veterans Affairs has been conducting a retrospective cohort mortality study of women Vietnam veterans. Military records were used to identify approximately 4600 women who served in Vietnam between July 4, 1965, and March 28, 1973, and a comparison cohort of nearly 5300 women who served during the same time frame but not in Southeast Asia or the Pacific theater. Current data include vital status determinations as of December 31, 1991, with a total of 532 deaths and an average follow-up of just over 20 years for both groups. Both the Vietnam and non-Vietnam women cohorts had a significant deficit of deaths from all causes compared to women in the US population. The two cohorts showed no difference in total mortality or in deaths from all cancers. A significant excess risk of pancreatic cancer was observed among Vietnam nurses compared to either non-Vietnam nurses (relative risk = 5.74) or women in the US population (standardized mortality ratio (SMR) = 2.78). Vietnam nurses also had an elevated risk of dying from cancer of the uterine corpus. Non-Vietnam nurses had a higher lung cancer mortality rate than women in the general population (SMR = 1.55) or nurses who served in Vietnam. Observed deficits of deaths from all causes and circulatory system diseases generally confirm a healthy selection bias for entry into and retention in the military that has been observed among men serving in the Armed Forces.