Primary Budd-Chiari syndrome is related to thrombosis of hepatic veins or the terminal portion of the inferior vena cava. This rare disease is usually caused by multiple concurrent factors, including acquired and inherited thrombophilias. Half of the patients with primary Budd-Chiari syndrome are affected with a myeloproliferative disease, the recognition of which is largely based on the assessment of V617F Janus tyrosine kinase 2 (JAK2) mutation in peripheral granulocytes. A diagnosis of Budd-Chiari syndrome should be considered in any patient presenting with acute or chronic liver disease, as clinical manifestations are extremely diverse. Spontaneous outcome in symptomatic patients is poor. Diagnosis can be made in most patients noninvasively when imaging shows venous obstruction and/or collaterals. A treatment strategy is recommended where anticoagulation is given first, followed by angioplasty when appropriate, then TIPS in patients not responding to previous measure, and finally liver transplantation. This strategy has achieved 5-year survival rates close to 90%.