The problems with first-generation stent grafts for endovascular aneurysm repair are well known, but their long-term outcome remains to be established. The purpose of the study was to characterize the outcome of patients treated for abdominal aortic aneurysm (AAA) with a first-generation stent graft, Vanguard (Boston Scientific, Natick, Mass), in a single academic center with a follow-up of up to 20 years. There were 48 AAA patients electively treated with a Vanguard stent graft between February 1997 and November 1999. The patients were monitored annually until the end of 2018. The outcomes were overall survival and the number of graft-related complications and reinterventions. The mean age was 70 years (range, 54-85 years), and the mean follow-up was 107 months (range, 6-262 months). All stent grafts were successfully implanted, but 90% of the patients encountered graft-related complications during follow-up. The most common complications were endoleaks (type I, 27%; type II, 29%; type III, 31%), stent fracture (46%), graft thrombosis (31%), and migration (40%). A total of 40 (83%) patients required a secondary procedure during long-term follow-up. The endovascular method for treating the complication was successful in 73 (87%) of 84 cases. There were no primary conversions, but 10 patients (21%) required a late conversion. In five cases, the complications required relining with a newer device. There were four AAA ruptures (8.3%), two of them fatal. The cumulative overall survival rates were 94%, 69%, 33%, 15%, and 13% at 1 year, 5 years, 10 years, 15 years, and 20 years, respectively. The use of the Vanguard, a first-generation stent graft, was associated with multiple graft-related complications. However, these complications could mainly be treated by endovascular means. The Vanguard stent graft is a good example of how new technology can cause unpredictable problems that can magnify the workload and endanger the patient's well-being even decades after the initial procedure. Copyright © 2019 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.