Hepatic encephalopathy is characterized by a wide spectrum of neuropsychiatric abnormalities and motor disturbances in patients with advanced liver disease. It is estimated to occur in 30% to 45% of patients with liver cirrhosis and in 10% to 50% of patients with transjugular intrahepatic portosystemic shunts. It can be seen in cancer patients due to multiple factors. Early diagnosis and treatment are important but can be challenging, especially in mild forms with subtle findings. This article reviews the pathogenesis, diagnostic criteria, grading, and management of hepatic encephalopathy.