A reputation data store provides reputation information to a user regarding the source of an electronic communication via a client. When the client receives an electronic communication, the client queries a reputation data store for reputation information regarding the source of the electronic communication. The client receives the reputation information from the reputation data store and displays the reputation information to the user. The user then decides whether to interact with the source of the electronic communication based on the displayed reputation information. Alternatively, an administrator may decide whether the user may interact with the source of the electronic communication.