We examined the electrophysiological correlates of the processing of social exclusion and inclusion by using a modified version of the Cyberball paradigm. Exclusion was found to be associated with a significant increase in the P3 complex. The frontal–central P3a was primarily related to the affective processing of rejection, whereas the late parietal P3b was associated with its perceived intensity. The expression of P3a and negative mood did also depend on the earlier experience; earlier inclusion affected the processing of exclusion, and vice versa. In conclusion, our data indicate that the complex process of social rejection can be tracked by using event-related brain potentials.