Wiggins, Harris and Lingoes, and Serkownek Minnesota Multiphasic Personality Inventory (MMPI) scores were used to predict Millon Clinical Multiaxial Inventory (MCMI) scores in a 100-patient sample. Equations from the first sample were cross-validated on a sample of 212 inmate subjects. We conclude that scores on 19 of the 20 MCMI scales can be successfully predicted by the Wiggins, Harris and Lingoes, and Serkownek subscales of the MMPI. In further cross-validation, the equations were used to predict the Morey, Waugh, and Blashfield MMPI composites for the prison sample, again with strongly positive results. The results appear quite promising for the estimation of personality disorder constructs from MMPI scales and subscales.