Data were obtained from the Denver Youth Survey in which adolescents and parents were interviewed annually between 1988 and 1992. The 1,395 adolescents included both serious chronic offenders and nonoffenders living in high-risk neighborhoods. Adolescents completed an abbreviated version of Eysenck's Empathy Subscale and Junior Impulsive Inventory. Gender differences indicated that females scored higher on empathy and guilt but that females also scored higher on opposite sex physical aggression and opposite sex confrontational aggression. Males scored higher on same sex physical aggression. Because of gender differences, the relationship of empathy and guilt to aggression was examined separately for males and females. Guilt, alone and in combination with empathy, predicted aggression for both sexes, although empathy was useful only in predicting opposite sex confrontation for males and same sex physical aggression for males and females. The finding of no gender differences in covert aggression, also referred to as social ostracism, contradicted previous research. Possible explanations for the results are discussed, and suggestions for future research are outlined. Empathy, guilt, and aggression items used in the study are listed in appendixes. 30 references and 7 tables