SummaryOne hundred and seventy-five offspring of parents in two psychiatrically ill groups and of normal controls in the New York High-Risk Project (NYHRP) were assessed for Axis II personality traits and disorders as defined by the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised (DSM-III-R). These offspring include: subjects at high risk for schizophrenia (HRSz, n = 48), all of whom have a parent with schizophrenic disorder; subjects at high risk for affective disorder (HRAff, n = 40), all of whom have a parent with affective disorder; and subjects at no increased risk for psychiatric illness (NC, n = 87), whose parents are psychiatrically normal.The trained interviewers, who administered a standardized direct interview, were blind to parental clinical status and to previous clinical status of the offspring.The rates for any personality disorder (PD) ranged from 7% to 20%. Comorbidity between Axis I and Axis II disorders was high for all groups.