Investigated preschool children's acceptance of the reciprocity norms that allow retaliation and that require returning favors. In 2 studies, Ss were shown cartoons that portrayed reciprocal or nonreciprocal aggressive and prosocial behavior; they were then asked for their evaluation of the actor and their attribution about the cause of his behavior. The 1st study with 31 36-68 mo olds employed a between-Ss design; the 2nd with 35 34-63 mo olds employed a within-S design. Although there were some significant differences in attributions for reciprocal and nonreciprocal behavior, there were no significant differences in evaluations. It therefore appears that preschool children do not accept reciprocity norms. (4 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1979 American Psychological Association.