Being able to judge the fairness of a personal encounter and having an appreciation of the associated feelings are important components of prosocial development. This study explored a common feature of everyday experience: unfair reward and unfair punishment. Scenarios depicting 4 possible variants of unfairness were read to children aged 9 to 11 years, who then made judgments regarding the degree of unfairness and the nature and strength of the feelings experienced by the characters. Our hypothesis that children with classroom conduct problems would judge the non-receipt of a deserved reward as worse than the receipt of an undeserved punishment was not confirmed. This differentiation, however, did prove to be characteristic of boys in general, but not girls. Being asked to think of unfair things that had actually happened did not appear to influence the children's responses to hypothetical unfair situations, but did reveal that children experience and remember a variety of unfair events in everyday family contexts. This study provides evidence that children actively monitor the receipt of social reward and punishment according to their perception of fairness.