Commercial γ-globulin given shortly before open-heart surgery and then one month later was ineffective in reducing the incidence of posttransfusion icteric hepatitis. There were 11 cases in 84 treated patients, 6 in 83 control patients. Half of the cases of hepatitis had an incubation period of less than 50 days and neither this nor the severity of disease was affected by the γ-globulin treatment.