This paper examines antisocial behavior in children and youth in relation to the biosocial personality theory of Hans Eysenck. It explains Eysenck's theory, which includes a significant role for biological factors in the development of antisocial behavior. The theory holds that three temperament traits--Psychoticism (P), Extroversion (E), and Neuroticism (N)--interact with the environment to produce personality. Eysenck's measurement instruments also contain a Lie (L) scale that has been shown to function as an index of socialization or social conformity. Individuals with antisocial behavior are predicted to be high on the P, E, and N scales. Individuals at greatest risk for developing antisocial behavior are predicted to have above average P-scale scores. Aggressive individuals are predicted to be higher on the E scale than on the N scale, and non-aggressive but antisocial individuals will be higher on the N scale than on the E scale. Individuals at greatest risk for antisocial behavior are also predicted to have below average L-scale scores. An overview of the theory, the possible basis for the temperament traits, and the research support for the prediction is discussed relative to children and youth with antisocial behavior. (Contains 56 references.) (Author/CR)