Background: The treatment of patients with complex aortoiliac disease (AID), classified as Trans-Atlantic Inter-Society consensus II (TASC) class C and D, presents a dilemma for vascular surgeons. Current guidelines recommend either open surgical reconstruction (OR), hybrid repair (HR) combining iliac stenting with femoral endarterectomy, or total endovascular repair (ER). While traditional OR with aortobifemoral bypass (ABF) is associated with excellent long term patency results, it is associated with significant perioperative morbidity with some studies citing mortality rates of up to 4-8%. The advancement of endovascular techniques has led to many trials suggesting that endovascular management of TASC II C and D lesions is a potential alternative treatment to open strategies mainly in the subset of patients with high surgical risk, given the substantially less perioperative morbidity and mortality compared to OR. Aim: The aim of this trial is to evaluate the short, mid-, and long-term results of open repair, hybrid and endovascular repair in the treatment patients with complex, TASC C and D, aortoiliac lesions. Methodology: This is a retrospective cohort study planning to include vascular surgery centers from the following countries: Italy, Portugal, Spain, and Serbia. Data will be collected on demographics, baseline comorbidities, anatomy and morphology of the aortoiliac and femoral bifurcation disease, intraoperative, postoperative, and follow-up data. Propensity score analysis will be performed by matching open repair patients in all three groups (open, hybrid, and endovascular repair) controlling for demographics, baseline comorbidities, anatomical and morphological data. Endpoints: Primary endpoints are all-cause mortality and the major adverse limb events (major amputation - below and above the knee, new onset acute limb ischaemia, reintervention of the treated arterial segment). The secondary endpoints are the 30-day complications and primary patency.