Endoscopic sclerotherapy of esophageal varices has been widely introduced in the treatment of portal hypertension. Two methods are applied: intravariceal injection obliterating portosystemic collaterals and paravariceal injection inducing subepithelial fibrosis. 90% of acute variceal bleedings are effectively controlled by both methods. In this respect, sclerotherapy may be superior to balloon tamponade. 10-20% of patients experience one of the following complications: esophageal ulcers and/or stenosis, pleural effusions, perforations and mediastinitis. The risk of recurrent variceal hemorrhage varies between 10 and 60 X 10(-3) per patient month depending on differences in patient characteristics and on the injection method used. Prophylaxis of recurrent variceal bleeding represents the only indication sufficiently supported by controlled trials. The reduced recurrence risk seems to correlate with a concomitant increase in long term survival. Encouraging data have been reported concerning the application of endoscopic sclerotherapy in acute variceal hemorrhage and as a prophylactic procedure in selected patients before the advent of first variceal bleeding. Furthermore, endoscopic sclerotherapy awaits controlled prospective comparison with elective portosystemic shunt surgery and medical treatment using beta-blocking agents.