The prevalence of abdominal aortic aneurysm (AAA) in Western Australia was studied using health department mortality data. Age-standardized and age-specific mortality rates related to the disease were calculated for the period 1980-88. The mortality rate has risen by 36 per cent for men and 24 per cent for women. Most of this rise was due to an increase in non-hospital and emergency admission hospital deaths. The number of elective and emergency operations has also risen. Despite two decades of elective surgery, the mortality rate for AAA continues to rise. This rise is highly suggestive of an increasing prevalence. This contrasts with the decline in deaths from other manifestations of arteriosclerosis and provides support for a policy of screening for aneurysm.