The life history data of each of sixty-six paranoid schizophrenics were evaluated to determine the degree to which each subject had been socially withdrawn before his psychotic breakdown. Each subject's present level of personality integration was determined by an evaluation of his clinical symptomatology and also by means of Rorschach evaluation. It was found that 'self-sealing-off' from socialization with others was not characteristic of the prepsychotic adjustment of the paranoid schizophrenics in this group. Those subjects who had relied most on social isolation for defense before their psychotic breakdowns were, both in terms of symptomatology and Rorschach evaluation, less disorganized than those who had not relied strongly on social isolation. Rigid self-isolation therefore appears to have high protective value for seriously disturbed personality structures.