SummaryA sample of adults (N = 44) was shown an edited videotape of episodes of playful and aggressive fighting involving middle school pupils that had previously been shown to a sample of 8 and 11 year‐old children. Each participant was asked to say whether she/he thought each episode was playful or aggressive and then to give the reasons for her/his choice. The majority view of the adults’ perceptions of the episodes matched the majority view of the children. As individuals, all 20 of the males and 22 of the 24 females showed significant agreement with the standard view of these episodes. Overall, the adults made significantly fewer errors than the 8 year‐olds had done, but did not differ in this respect compared to the 11 year‐olds. Adult males in this study were more likely to mistakenly view aggressive episodes as playful than to mistakenly view playful episodes as aggressive, with the opposite being the case for adult females. Among the adults, the most frequently reported criteria for deciding upon the nature of the episodes were the nature of the physical actions, inferences about action/intent, facial expressions, and whether the children in the episodes remained together or separated after the interaction. The results are discussed in terms of their implications for playground supervision and behaviour management.