In 1963, the first human liver transplant was performed.1 However, 1-year survival of liver transplant recipients would not be achieved until 1967. Since then, the success and volume of liver transplantation has grown at a dramatic pace with the evolution of surgical techniques and medications. In 2020, nearly 9,000 liver transplants were performed in the United States and over 98,000 patients were living with functional liver grafts.2 While liver transplantation remains the only curative therapy for end-stage liver disease, it is technically complex and associated with an array of potential complications. In general, venous outflow and portal venous complications are relatively uncommon compared with hepatic arterial or biliary complications, but they are associated with high morbidity and mortality.3 Venous outflow complications (VOC) include hepatic venous outflow or inferior vena cava stenosis whereas portal venous complications include portal vein stenosis, portal vein thrombosis, and recurrent cirrhosis with portal hypertension.3 Treatment of venous complications following liver transplantation is challenging and obtaining the best outcome is not always straightforward. There are many factors to consider including patient related factors, not least among these being the patient's profoundly deconditioned state secondary to their disease and inability to tolerate another major surgical insult, anatomic factors, and diagnostic challenges. These questions and formulating the best plan warrant a collaborative discussion between surgical and interventional colleagues to optimize outcomes. While early postoperative management of these venous complications has traditionally been managed operatively, advances in interventional techniques have contributed significantly to the management and outcomes with endovascular diagnosis and treatment of an increasing proportion of post-transplant VOC and portal venous complications, which are reviewed herein.