The purpose of the study was to examine the relationship of the limitation and outcome of simultaneous speech to those dimensions of personality indexes by Cattell's 16PF Questionnaire. More than 500 conversations of 24 female college students were computer-analyzed for instances of simultaneous speech, and the frequencies with which they initiated interruptive and noninterruptive simultaneous speech were compared to their 16PF scores and those of their conversational partners by means of hierarchical multiple regression analyses. The results suggest that the personalities of both participants in a conversation influence the initiation of each participant's simultaneous speech but not its outcome. (Author)