In this article we suggest a mechanism for norm regulation that does not rely on explicit information exchange or costly reinforcement, but rather on the sensitivity of group members to social cues in their environment. We examine whether brief conversational silences can (a) signal a threat to one's inclusionary status in the group and (b) motivate people to shift their attitudes to be in line with group norms. In two experimentsusing videotaped and actual conversations, respectivelywe manipulated the presence of a brief silence after group members expressed a certain attitude. As predicted, attitudes changed relative to the norm after such a brief silence. Those highly motivated to belong changed their attitude to become more normative, whereas those less motivated to belong shifted away from the group norm. The results suggest that social regulation may occur through very subtle means.