Many successful career women fail to reach their full potential because of the imposter phenomenon, an inabiltiy to experience themselves as successful career persons. Career women were studied to investigate variables which may be used to predict the imposter phenomenon and also to test the hypothesis that successful career women who are able to attribute their successes to internal factors, e.g., ability, may suffer less from the effects of the imposter phenomenon. Successful women (N=80) in traditionally masculine careers completed questionnaires containing five scales (perception of self, acceptance of self, perception of career success, tolerance for ambiguity, and perception of parental career orientation) and demographic questions. Results showed that discrepancies between self-perceptions of the ideal person in one's field, retrospective perceptions of parental career orientation, and attributions of causality for career success contributed significantly to the prediction of the imposter phenomenon. The findings suggest that successful career women who suffer from the phenomenon have not identified and internalized those aspects of themselves that have been responsible for their career achievements. (PAS)