The U.S. military special operations communities continually seek exemplary trainees to undertake the extremely arduous, grueling and costly training, and upon successful completion, operate in stressful and dangerous environments. The military has refined the requisite physical and mental capabilities of trainees but could be lacking another component, the essential personality traits needed to succeed in these hazardous career fields. The study was conducted to determine if there was a relationship between the 24 scales in the Millon Index of Personality Styles assessment and the performance of students undertaking specialized dive training. This study of the personality traits of 300 Explosive Ordnance Disposal and Marine Corp reconnaissance student divers investigated the performance of student Divers. A robust assessment tool, the Millon of Personality Styles was administered to 10 diver classes. Upon identification of specific personality traits, these characteristics could then be used to develop a standard selection process to to help predict the potential success of Diver candidates. Study findings lend strong support for the use of this type of assessment.