We experimentally study the social transmission of “inconvenient” information about the externalities generated by one’s own decision. In the laboratory, we pair uninformed decision makers with informed senders. Compared to a setting where subjects can choose their information directly, we find that social interactions increase selfish decisions. On the supply side, senders suppress almost 30 percent of “inconvenient” information, driven by their own preferences for information and their beliefs about the decision maker’s preferences. On the demand side, about one-third of decision makers avoids senders who transmit inconvenient information (“shooting the messenger”), which leads to assortative matching between information-suppressing senders and information-avoiding decision makers. Having more control over information generates opposing effects on behavior: selfish decision makers remain ignorant more often and donate less, while altruistic decision makers seek out informative senders and give more. We discuss applications to information sharing in social networks and to organizational design.