Both the original Millon Clinical Multiaxial Inventory (MCMI-I; Millon, 1977) and the Millon Clinical Multiaxial Inventory-II (MCMI-II; Millon, 1987) were refined and strengthened on a regular basis by both theoretic logic and research data. This aspiration has continued. The new Millon Clinical Multiaxial Inventory-III (MCMI-III; Millon, 1994) has been further coordinated with the most recent official diagnostic schema, the Diagnostic and Statistical Manual of Mental Disorders (4th ed., [DSM-IV]; American Psychiatric Association [APA], 1994) in an even more explicit way than before. Although the publication of the first version of the MCMI preceded the publication of the DSM-IV, its author played a major role in formulating the official manual's personality disorders, contributing thereby to their conceptual correspondence. The DSM-III-R (APA, 1987) was subsequently published in the same year as the MCMI-II; the inventory was modified in its final stages to make it as consonant as possible with the conceptual changes introduced in the then forthcoming official classification. The present version of the MCMI, the MCMI-III, strengthens these correspondences further by drawing on many of the diagnostic criteria of the DSM-IV to serve as the basis for drafting the inventory's items. This article reports on a select set of theoretical and empirical developments that are being carefully weighed for possible inclusion in future MCMIs, or as a guide in the refinement process of future MCMIs.