Although personnel selection processes for Basque civil servants often involve the assessment of personality, there are currently no Basque self-report instruments that provide valid and reliable measures of the Big-Five factors of personality. The aim of this study was to validate the Basque version of the Revised NEO Personality Inventory (NEO PI-R; Costa & McCrae, 1992 ), by examining its psychometric properties. We assessed the dimensionality of the instrument, the convergent and discriminant validity, the temporal stability, and the internal consistency of each dimension. Relationships between NEO PI-R domains and other variables (i.e., gender and age) were also examined. The sample was composed of 1,790 participants (1,031 women and 759 men), whose ages ranged between 16 and 65. Results suggest that the Basque version of NEO PI-R allows assessing personality from the Big-Five framework in a valid and accurate way. The age and gender pattern of personality domains are in consonance with previous findings in other cultures, notably with those observed in Spanish samples.