We bring up to date our series of direct measurements of portal flow and pressure in patients with cirrhosis of the liver. In 153 patients the portal flow averaged 447 plus or minus 350 ml. Hg per minute and the portal pressure 28.5 plus or minus 4 mm. Hg (approximately 387 mm. H2O). Both quantities compare favorably with our previous measurements in smaller groups of patients. In 80 of our patients we had also measurements of pressure on the hepatic and splanchnic sides of a clamp occluding the portal vein. Nine of these patients had an hepatic occluded portal pressure higher than either or both the free portal pressure and the splanchnic occluded portal pressure. Of these nine patients with reversed pressure differences, two had stagnant portal flow and the remaining seven had forward flow into the liver measuring from 80 to 1,116 ml. Hg per minute.