Considerable evidence has accumulated that alterations in the direct current fields of the brain can produce alterations in function (O'Leary and Goldring, 1964). In view of this a group of investigators instituted a clinical trial of the possible usefulness of transcranial polarization (Lippold and Redfearn, 1964; Redfearn et al., 1964; Costain et al., 1964). In the approach used a current was passed between electrodes attached just superior to the eyebrows and an electrode on the leg. The principal changes reported consisted of an elevation of mood and an increase in involvement with the environment when the head was positive relatively to the leg and a withdrawal and quietness when the head was negative relatively to the leg. The current level reported as effective was generally of the order of 250 microamperes. Among Lippold and Redfearn's subjects were seven schizophrenics, in six of whom brief D.C. polarization produced the expected effects. Among the subjects of Redfearn et al. were four schizophrenics, in all of whom some favourable effect from D.C. head positive polarization was reported. This study was uncontrolled. In a blind controlled trial, Costain et al. found head-positive polarization to be of therapeutic efficacy in a group of 24 depressed patients. Their interpretation of results was challenged by Dawson and Montagu (1965). In view of these reports, we decided that a pilot study of the possible efficacy of transcranial polarization in altering the non-responsive state of chronic schizophrenic patients was warranted. It was decided that a more longitudinal study would be of greater value in determining possible therapeutic usefulness than a shorter trial on a larger number of patients. The experiment was conducted on one of the research wards of Rockland State Hospital.