This study examined the social effects of emotions related to supplication and appeasement in conflict and negotiation. In a computer-simulated negotiation, participants in Experiment 1 were confronted with a disappointed or worried opponent (supplication), with a guilty or regretful opponent (appeasement), or with a nonemotional opponent (control). Compared with controls, participants conceded more when the other experienced supplication emotions and conceded less when the other experienced appeasement emotions (especially guilt). Experiment 2 replicated the effects of disappointment and guilt and showed that they are moderated by the perceiver's dispositional trust: Negotiators high in trust conceded more to a disappointed counterpart than to a happy one, but those with low trust were unaffected. In Experiment 3, trust was manipulated through information about the other's personality (cooperative vs. competitive), and a similar moderation was obtained.