Investigated the mechanisms of decision making under ambiguous circumstances and under known risk related circumstances for the perfectionist. High personal standards and the desire to avoid mistakes tend to guide the perfectionist to nonrisky decisions. In ambiguous situations, no standard for positive/negative outcomes are provided, leaving the perfectionist no direct method to gauge the potential for error. The perfectionist is then left to previous experience and learned response in the process of decision making. The test group included 58 healthy individuals (aged 19-68 years). Neuropsychological background testing and personality questionnaires were used to assess personality traits to determine behavioral inhibition and behavioral approach. The Game of Dice Task (GDT) assessed decision making under risk and the Iowa Gambling Task (IGT) assessed decision making under ambiguous circumstances. Neuropsychological tasks are not strongly associated with personality traits. Testing supported the thought that when known risks are presented, decision making follows a nonrisk pathway. Perfectionist attributes long considered to be detrimental are actually a benefit in decision-making behavior.