Objective: In contrast to endovascular repair (EVAR), the absence of rigorous imaging follow-up after open surgical repair (OSR) has rendered the perception that late failure (LF) is rare. Better understanding of associated factors with LF will help define OSR follow-up paradigms and perhaps alter initial repair strategy to facilitate treatment of LF. The aim of this study is to evaluate aspects of LF requiring intervention after OSR. Methods: From 1998 to 2008, data were collected prospectively on 1097 patients who underwent an aortic endovascular repair. Patients undergoing intervention for LF contiguous with prior OSR were subjected to further analysis. The indication for reintervention was a maximal diameter >60 mm. Univariable and multivariable linear regression models were used to compare patients and disease variables (18 variables regarding age, comorbidities, family history, etiology, and extent) with time to LF. Results: LF of open surgical aneurysm repair was identified in 104 (9.5%) patients. Mean aneurysm diameter was 72 ± 12 mm. Mean age at first repair and time between the two repairs were 61.4 ± 10.0 and 10.8 ± 6.0 years, respectively. When compared with the 993 other patients whose EVAR was their primary repair, LF patients were significantly younger at the time of their first repair (61.4 ± 10.0 vs 74.1 ± 9.6 years; P < .00001) and more frequently had a family history of aneurysms (20% vs 7%; P = .001). They were also more likely to have presented with dissection, renal insufficiency, and manifestations of atherosclerosis. On multivariable analysis, patients with an initial incomplete OSR (aneurysm located in another aortic segment but not treated at the time of the primary repair), more extensive aneurysms (those involving the descending thoracic or the thoracoabdominal aorta), and older patients experienced earlier LF (P < .00001, .002, and .001, respectively). Although we were incapable of determining the incidence of LF after OSR, 34% of patients presenting with LF were regional to our center. Conclusion: Aneurysmal disease is an ongoing process potentially involving the entire aorta. Segments that appear normal prior to OSR of EVAR may be vulnerable to LF. We identified several groups of patients following OSR who mandate more aggressive follow-up given their propensity to present with LF. The threshold and strategies guiding reintervention in the setting of LF is dependent upon many factors relating to the structure and the morphology of the aorta and implanted graft, the type of anastomosis, and patient comorbidities. Therefore, surgeons should consider LF treatment options when planning an aneurysm repair in an effort to optimize any later interventions, and have specifically tailored follow-up paradigms. © 2010 Society for Vascular Surgery.