In examining extraversion, neuroticism, psychoticism, depression, anxiety, excitability, and aggressiveness, the question of interest is to identify what personality traits should be studied in-depth by criminologists to assess the relation between personality and deviant behavior. Personality traits are measured by the Freiburg Personality Inventory developed by West Germany's Max Planck Institute. The issue of prisonization is also addressed to obtain further indications of the validity of personality factors in criminality. Theoretical findings indicate that extraversion has a very minor influence on deviant behavior. While neuroticism enables sufficiently strong relations to be recognized, such relations should not be viewed as confirming Eysenck's theory on criminality. It may be useful to place greater emphasis on observing neuroticism from the perspective of depression on the one hand and anxiety on the other. The utility of the anxiety trait in criminological research is substantiated. Further, arousal and excitability are highly significant features in the study of deviant behavior. It is concluded that an individual's personality has a causal and relevant effect on tendency toward deviant behavior and that anxiety and aggressive excitability are high predictors of deviant behavior. 66 references, 4 tables.