Previous research has argued that people exclude others when their inclusion does not increase their payoffs in multiparty negotiations. However, the majority of this research has been conducted in settings where participants do not interact person-to-person or where they communicate through highly restricted means. the authors argue that this view on exclusion needs to be modified and propose that communication can induce cooperation and thereby influence social exclusion in multiparty negotiations. Data from two experiments examine how an opportunity to detect others’ emotions, words, and behavior affects cooperation and social exclusion in multiparty negotiations. Study 1 shows that negotiators who communicate face-to-face or in the same (chat) room, exclude others less frequently. Study 2 replicates this effect and also shows that these effects are due to increased cooperation displayed in negotiators’ language and behavior.