structure of MCMI-III personality disorders has between 2 and 4 factors. Methods: The present study used a large sample of 674 non-clinical subjects divided at random in two groups: a) calibration, and b) validation. In the calibration group, principal component analysis with orthogonal rotation was carried out, obtaining 2, 3 and 4 factors for the overlapping and non-overlapping scales independently. In the validation group, the three models were compared using confirmatory factorial analysis techniques. Results and Conclusions: The exploratory and confirmatory results indicate that the 4-factor solution is the most plausible. Although the congruence coefficients between non-overlapping and overlapping scales in the 4-factor solution were higher, confirmatory factor analysis showed that models designed from overlapping scales did not fit well to data.