Hepatorenal syndrome is a serious complication of end-stage cirrhosis characterized by increased splanchnic blood flow, a hyperdynamic state, reduced central volume, activation of vasoconstrictor systems, and extreme renal vasoconstriction leading to a decrease in GFR. In recent years, the role of systemic inflammation, a key feature of cirrhosis, in the development of hepatorenal syndrome has been emphasized. The mechanisms by which systemic inflammation induces changes in renal blood flow during hepatorenal syndrome remain to be elucidated. Early diagnosis is central to treatment, and recent changes in the definition of hepatorenal syndrome help to identify patients at an earlier stage. Vasoconstrictor agents such as terlipressin and albumin are the first-line treatment options. Several controlled studies have shown that terlipressin is effective in reversing hepatorenal syndrome and may improve short-term survival. Not all patients respond, and even those who do have a very high early mortality rate without liver transplantation. Liver transplantation is the only definitive treatment for hepatorenal syndrome. In the long term, transplant patients with hepatorenal syndrome usually have a lower GFR than patients without hepatorenal syndrome. Differentiating hepatorenal syndrome from acute tubular necrosis (ATN) is often a difficult but important step, as vasoconstrictor drugs are not warranted in the treatment of ATN. Hepatorenal syndrome and ATN can be considered a continuum rather than separate entities. Emerging biomarkers may help distinguish between these two conditions and provide prognostic information about renal recovery after liver transplantation and potentially influence the decision for simultaneous liver and kidney transplantation.