Cloninger's dimensional psychobiological model of personality accounts for both normal and abnormal variation in 2 major personality components: temperament and character. Here, we examined the psychometric properties of the Turkish version of the Temperament and Character Inventory (TCI) in a healthy Turkish population, obtaining normative data for the Turkish TCI. The study was conducted in healthy volunteers at both Karadeniz Technical University School of Medicine and Ataturk University School of Medicine (n = 633). The Turkish sample had significantly lower mean scores on Novelty Seeking and Reward Dependence and higher mean scores oil Harm Avoidance than the American sample. The Turkish sample had significantly lower scores on Self-Directedness, Cooperativeness, and Self-Transcendence. Self-Directedness and Harm Avoidance, Cooperativeness and Reward Dependence, and Cooperativeness and Self-Directedness were intercorrelated. The Cronbach coeficients were between 0.60 and 0.85 on temperament dimensions, and between 0.82 and 0.83 on character dimensions. The lowest Cronbach coefficients were found in Reward Dependence (0.60) and Persistence (0.62). A principal axis factor analysis with a 4-factor solution revealed the highest loadings on Novelty Seeking and Harm Avoidance and relatively weaker loadings on Reward Dependence and Persistence. A 3-factor solution for character subscales indicated the highest loadings on Cooperativeness and Self-Transcendence. The factorial structure was consistent with Cloninger's 7-factor model of personality, and test-retest indicated a good stability of scores over time. The reliability and factorial validity of the Turkish version of the TO are therefore supported. Published by Elsevier Inc.