Introduction: The purpose of this article is to describe a standardized approach for creating a physician-modified endovascular graft (PMEG) based on the Zenith Flex (R) (Cook Medical Inc., Bloomington, Indiana) platform. Technique: A sterile template is constructed based on computed tomography angiography (CTA) measurements. Once the Zenith Flex (R) bifurcated endograft is desheathed, the template is placed over the device and adjusted so that the planned fenestrations do not overlap with the struts. The fenestration locations are marked on the fabric of the endograft and created using high-temperature cautery. The distal part of a snare is obtained, braided around a modified angiometer with a diameter matching the fenestration, and secured around the corresponding fenestration with locking sutures. Diameter-reducing ties are added by first securing a suture loop at the 12 o'clock position of each Z-stent, then the trigger wire is repositioned to the outside of the endograft at the 6 o'clock position and threaded through each of the loops to constrain the Z-stents. The endograft is reloaded through the peel-away sheath and is ready for the procedure.SAERS/HUISTRA/ALRAWI/ZEEBREGTS/LIND/FORSSELL Conclusion: A PMEG with diameter-reducing ties and reinforced fenestrations can be constructed in a standardized fashion using the Zenith Flex (R) platform, providing an endovascular treatment option for complex abdominal aortic aneurysms when custom-made endografts are unavailable. Clinical impact: Fenestrated endovascular aortic repair is an important treatment option for complex abdominal aortic aneurysms. However, custom-made fenestrated devices may not be available in all regions or medical centres, and their use is limited in urgent situations. Familiarity with constructing a physician-modified endovascular graft can provide patients with an endovascular treatment option in such situations. This step-bystep guide to constructing a physician-modified endovascular device based on the Zenith Flex (R) platform can help surgeons create a bespoke fenestrated device with diameter-reducing ties and reinforced fenestrations in a standardized fashion within a matter of hours.