Peritoneovenous shunts (LeVeen type) were implanted in seven patients with cirrhosis complicated by ascites refractory to diuretic treatment. Three patients died of gastrointestinal bleeding and hepatic coma 1 to 7 weeks after the shunt implantation. The patients who died were those with the most severely impaired liver and kidney function. In two of the four surviving patients (observation time, 5-24 months) the shunt was patent during the observation time, and ascites disappeared. In the other two the shunt closed, in one patient repeatedly following several re-implantations. Enhanced urinary sodium excretion was observed in patients with patent shunts. After disappearance of ascites, the splanchnic venous pressures became less deranged. Long-term change in plasma volume or circulating albumin mass could not be detected. A patent shunt increases the drainage from the peritoneal cavity, but detectable increment in the overall lymph drainage was only found in a patient with a very low pre-shunt value. The findings do not support the 'overflow' theory of ascites formation but rather the 'lymph imbalance' theory. For clinical evaluation of peritoneovenous shunting in the treatment of ascites a controlled clinical trial is essential.