Background: The effect on outcome of the introduction of endovascular techniques for the exclusion of abdominal aortic aneurysm (AAA) is largely unknown. The alm of the study was to contrast the early and mid-term outcome after open and endovascular AAA repair. Methods: Consecutive patients who underwent transfemoral endovascular aneurysm repair (EVAR; n = 93) between April 1998 and January 2003, or conventional open aneurysm repair in e time intervals before (n = 113) and after (n = 82) the introduction of EVAR were studied. All data were collected prospectively. All patients underwent elective and primary repair. Patient survival was calculated by die Kaplan-Meier method and the possible predictive value of more than 25 perioperative variables on five outcome variables (length of intensive care unit stay, morbidity, and 30-day, 6-month and overall mortality) was assessed by multivariate analysis. Results: There were no differences in risk profiles between the three groups. Selection for EVAR was based on anatomical grounds only. All five outcome variables were significantly better with EVAR than either former or recent open repair. The only significant predictors of failure were advanced age and the need to perform an additional procedure for former open repair; hypertension and the preoperative use of anticoagulants for recent open repair; and renal insufficiency and pulmonary insufficiency for EVAR. Conclusion: EVAR offered considerable benefits compared with conventional open repair at early and mid-term follow-up, which was not explained by selection of patients with a favourable risk profile. In the current era, in which patients are selected for open repair as a consequence of unfavourable anatomy, morbidity and mortality rates following conventional open treatment of AAA have increased at early and mid-term, but not at long-term, follow-up.