Percutaneous transhepatic catheterization of the portal venous system and pressure readings were performed in nineteen patients with cirrhosis of the liver and bleeding varices. Portal pressures were recorded in awake and mobile patients in supine, sitting and standing position, during sleep, ingestion of food, Valsalva manoeuvre and coughing. No significant differences were recorded in the different postures, during sleep or food intake. Four patients with hepatofugal portal blood flow had, however, lowest pressure in standing position. During Valsalva manoeuvre portal pressure was doubled, and it became fourfold during coughing. Elevations of this magnitude have not previously been reported. A relationship was found between portal pressure and size of varices.