It is widely acknowledged that trust greatly affects work group functioning. Whereas trust may facilitate cooperation, distrust may impede it. Insight into when distrusters may be prompted to cooperate may therefore be of importance. Empirical studies point to several moderators of the effect of trust on cooperation. Unfortunately, these studies largely ignored the potential role of group member affect. Our study shows that group members' affective displays (particularly the activation level of the displays) have a substantial impact on the relationship between trust and cooperation. First, a scenario experiment (n=80) revealed that low trusting individuals were more willing to cooperate when confronted with group members who display high (versus low) activation affective states, whereas for more high trusting individuals cooperation was not contingent on other group members' affective displays. Second, a laboratory experiment (n=78), employing a social dilemma paradigm, replicated these findings and indicated that this effect is explained by the extent to which others are expected to cooperate. The discussion focuses on theoretical implications and managerial ramifications. Our study testifies to the significant role that affect may play in keeping up cooperation in organizations and work groups when trust is withering. © 2009 British Academy of Management.