One of the official proposals for the fifth edition of the American Psychiatric Association's diagnostic manual (DSM-5) is to provide a dimensional model in which 37 traits are included within six broad domains. One of the more important traits within this model is ‘histrionism’ because another proposal for DSM-5 is to delete the histrionic diagnostic category. The only way to recover histrionic traits in DSM-5 will be through the dimensional model. Histrionism, though, is included within the domain of antagonism of this dimensional model, despite the fact that previous research has consistently placed histrionic personality disorder within extraversion. The current study tests empirically whether histrionic personality traits are optimally placed within the domain of extraversion or antagonism through tests involving seven alternative measures of histrionic personality disorder, five scales to assess the DSM-5 components of histrionism, 10 measures of various histrionic personality traits and two alternative measures of extraversion. The results of the study provide support for placing histrionism within antagonism and clarify the inconsistency of the DSM-5 placement with the existing research, but also indicate that a more complete and accurate understanding of histrionism would include extraversion. The implications of the findings for DSM-5 and future research are discussed. Copyright © 2010 John Wiley & Sons, Ltd.