The most common variant of iliocaval compression occurs when the left common iliac vein is compressed between the right common iliac artery and the lumbosacral spine, termed May–Thurner Syndrome (MTS) or Cockett's syndrome. Aside from effacement of the vein, arterial pulsations cause vascular thickening, intimal proliferation, and fibrous adhesions that can result in venous obstruction. Patients may present with nonthrombotic MTS, acute deep venous thrombosis (DVT), or chronic occlusion of the left common iliac vein. Correspondingly, clinical symptoms range from sudden onset of left lower extremity swelling with DVT to less dramatic presentations of chronic venous disease including edema, pain, varicose veins, pigment changes, ulcers, or other stigmata of postthrombotic syndrome. Endovascular approaches with pharmacologic and mechanical thrombolysis, intravascular ultrasound (IVUS), and self-expanding stents have resulted in high clinical success rates in the treatment of MTS.