Psychometric tests were administered to 36 alcoholic patients with cirrhosis without overt portal systemic encephalopathy and to 32 alcoholics without liver diseases. Verbal ability was preserved in both groups. The cirrhotic patients scored worse than the alcoholics without liver disease on most of the tests of psychomotor performance. Based on the three most discriminative tests, 50% of the cirrhotic patients had one or more scores that were more abnormal than those of any member of the alcoholic group. Significant correlations were found between the severity of liver disease and most tests of performance in the cirrhotic group, due primarily to the influence of serum albumin as a component of the severity index. We conclude that psychomotor tests are sensitive tools for the detection of latent encephalopathy, and that nutritional status probably plays a role in determining test performance.