The HEXACO model (Lee & Ashton, 2004, 2006) of personality structure is based on 6 dimensions that have been recovered in lexical studies of personality in various languages. In this study, we examined a Dutch version of the HEXACO Personality Inventory (HEXACO-PI; Lee & Ashton, 2004) and found it to have satisfactory psychometric properties. Additionally, we examined the level of self-other agreement for the HEXACO-PI variables and the relation of HEXACO-PI Honesty-Humility with the Self-Report Psychopathy Scale (Williams, Paulhus, & Hare, 2007) at varying levels of self-other acquaintanceship. Self-other agreement was found to be high, especially among dyads with high levels of acquaintanceship. Self-reported and other-reported Honesty-Humility and Emotionality were the strongest predictors of psychopathy. The relation between other-reported Honesty-Humility and self-reported psychopathy was near zero for dyads with low levels of acquaintanceship but was moderately strong for dyads with high levels of acquaintanceship. Copyright © Taylor & Francis Group, LLC.