ABSTRACT Two studies examined the relation between narcissism, self-concept clarity, negative emotions, and aggression based on theoretical assumptions proposed by Baumeister, Smart, and Boden (1996). Narcissism and self-concept clarity were examined as predictors for anger, depression, and verbal aggression following ego-threat, which was operationalized by a bogus performance feedback on an intelligence test. The second study also examined the mediating effects of participants' negative emotions to provide an additional explanation for the aggressive reactions after failure. As expected, narcissism and self-concept clarity were significant predictors of negative emotions and aggression after failure. In accordance with our hypothesis, high narcissists with low self-concept clarity reacted with anger and aggression after failure, whereas less narcissistic individuals with high self-concept clarity showed feelings of depression and no aggression. The results also indicated that aggression was always directed toward the source of the ego-threatening feedback. Additionally, anger and depression could predict the aggressive response after failure but they did not mediate the relation between narcissism, self-concept clarity, performance feedback, and aggression.