The Millon Clinical Multiaxial Inventory – Fourth Edition (MCMI-IV) is the most recent edition of the Millon Clinical Multiaxial Inventory. The MCMI is a psychological assessment tool intended to provide information on personality traits and psychopathology, including specific mental disorders outlined in the DSM-5. It is intended for adults (18 and over) with at least a 5th grade reading level who are currently seeking mental health services. The MCMI was developed and standardized specifically on clinical populations (i.e. patients in clinical settings or people with existing mental health problems), and the authors are very specific that it should not be used with the general population or adolescents. However, there is evidence base that shows that it may still retain validity on non-clinical populations, and so psychologists will sometimes administer the test to members of the general population, with caution. The concepts involved in the questions and their presentation make it unsuitable for those with below average intelligence or reading ability. The MCMI-IV is based on Theodore Millon's evolutionary theory and is organized according to a multiaxial format. Updates to each version of the MCMI coincide with revisions to the DSM. The fourth edition is composed of 195 true-false questions that take approximately 25–30 minutes to complete. It was created by Theodore Millon, Seth Grossman, and Carrie Millon. The test is modeled on four categories of scales: 15 Personality Pattern Scales 10 Clinical Syndrome Scales 5 Validity Scales: 3 Modifying Indices; 2 Random Response Indicators 45 Grossman Personality Facet Scales (based on Seth Grossman's theories of personality and psychopathology) Theory The Millon Clinical Multiaxial Inventories are based on Theodore Millon's evolutionary theory. Millon's theory is one of many theories of personality. Briefly the theory is divided into three core components which Millon cited as representing the most basic motivations. These core components are which each manifest in distinct polarities (in parentheses): Existence (Pleasure – Pain) Adaptation (Passive – Active) Reproduction (Self – Other) Furthermore, this theory presents personality as manifesting in three functional and structural domains, which are further divided into subdomains: Behavioral Phenomenological Intrapsychic Biophysical Finally, the Millon Evolutionary Theory outlines 15 personalities, each with a normal and abnormal presentation. The MCMI-IV is one of several measures in a body of personality assessments developed by Millon and associates based on his theory of personality. History MCMI In 1969, Theodore Millon wrote a book called Modern Psychopathology, after which he received