Budd-Chiari Syndrome is a rare, challenging clinical condition which is characterised by a hepatic venous outflow obstruction, usually caused by a thrombotic occlusion at the level of the small hepatic veins until the entrance of the inferior vena cava into the right atrium. It affects usually young adults, mostly female. The classical clinical presentation is a triade of abdominal pain, hepatomegaly and ascites, but usually, there are large inter-individual differences ranging from asymptomatic cases to patients with portal hypertension or even liver failure. Budd-Chiari syndrome can be classified in a primary form, typified by an endoluminal lesion of mostly thrombotic origin, and a secondary form, characterised by an extravascular lesion invading or compression the lumen. The aetiology is complex and multifactorial, and usually consists of a combination of underlying inherited and acquired thrombophilia. Among the main causes are myeloproliferative disorders, Factor V Leiden mutation, prothrombine gene mutation and deficiencies of natural coagulation inhibitors, but also antiphospholipid syndrome and use of oral contraceptives. The outflow obstruction, resulting in increased sinusoidal pressure causes centrilobular congestion and ischaemia, with a decrease in portal inflow. Therapeutic options range from conservative measures to derivative procedures and eventually liver transplantation. Anticoagulation seems mandatory to prevent further ungoing thrombosis but should be used with caution when there is a history of variceal bleeding. Hepatic vein angioplasty, vascular stents and thrombolysis can be attempted in patients with a short history of thrombosis. Surgical portosystemic shunting was commonly used in the past as a derivative procedure to convert the portal vein from an inflow to an outflow tract. The rationale for this type of shunting is decreasing since the introduction of the TIPS, which shows promising results in the treatment of Budd-Chiari Syndrome, especially when covered stents are used. Liver transplantation is reserved for patients with end-stage liver disease. The overall 5-year survival in Budd-Chiari Syndrome currently ranges from 64-69%. Age, renal function and the Child-Pugh score and its components appear to be of prognostic value to assess disease severity in terms of survival probabilities.