Abstract: Methods, systems, and apparatuses, including computer programs encoded on computer-readable media, for receiving from responders conversation selection criteria and mode of communication information. A request for a conversation is received, from an initiator using a first communication mode, that identifies a topic, but does not identify any responders. A conversation identifier is created. Possible responders are determined based on the topic and the conversation selection criteria. The topic of the conversation is sent to the possible responders, without identifying the initiator. A first response from a first responder is received using a second communication mode that is different than the first communication mode. The first response is mapped to the conversation based in part on the conversation identifier. The response is sent to the initiator using the first communication mode.