Objective: Recent reports showed that the Endurant stent graft (Medtronic Cardiovascular, Santa Rosa, Calif) is safe and effective for endovascular repair of abdominal aortic aneurysms (AAAs). However, due to its relatively recent introduction, only short-term follow-up data are available. This study presents the 4-year results using this device. Methods: All clinical data, including detailed anatomic information of the first 100 consecutive patients treated with the Endurant stent graft for an infrarenal AAA in three Dutch high-volume hospitals, were prospectively collected. Computed tomography angiography was routinely performed before the procedure, <= 1 month, and at 1 year post-endovascular aneurysm repair. Thereafter, the imaging modality during yearly follow-up was individualized (duplex ultrasound imaging or computed tomography angiography). Patients were classified as within or outside the instructions for use (IFU) for analysis. Study end points were primary clinical success, overall and AAA-related mortality, and sac morphology changes and endoleak during follow-up. Estimates were obtained using Kaplan-Meier plots. Results: The study included 100 consecutive patients (88 men) with a median age of 74 years (interquartile range [IQR], 67-79 years) and median AAA diameter of 58 mm (IQR, 55-65 mm), between December 2007 and March 2009. Twenty patients (20%) were treated outside the IFU (18, outside proximal neck IFU, one outside iliac IFU, and one outside both IFUs). Median follow-up was 48 months (IQR, 36-53 months), and no patients were lost. One contained rupture was observed after 1.5 months due to graft infection. No patients had graft migration. Two type Ia endoleaks, 5 type Ib endoleaks, and 15 type II endoleaks were found. Primary clinical success was 97%, 90%, 84% and 77% at 1, 2, 3, and 4 years, respectively. Primary clinical success was comparable for patients treated within or outside IFU (P = .20), although both patients outside iliac IFU needed a secondary iliac intervention. Over time, maximum aneurysm diameter decreased >= 5 mm, remained stable, and increased >= 5 mm in 58%, 32%, and 10% of the patients, respectively. All-cause mortality was 20% at 4 years, with a 3% AAA-related mortality. Conclusions: The 4-year follow-up data of the Endurant stent graft for AAA treatment shows its use results in a low AAA-related mortality with adequate prevention of rupture or aneurysm growth. Although patients with very challenging anatomy were treated in our series, primary clinical success rates were comparable for patients treated within and outside the IFU. However, both patients outside the iliac IFU needed a secondary iliac intervention. The knowledge of the present results may aid in improving outcomes in the future.