Strategies are described for establishing a peer-to-peer (P2P) direct coupling channel between two user devices at the commencement of an Instant Messaging (IM) conversation. Provisions are described for gracefully switching to a switchboard coupling channel when the conversation includes more than two participants, and switching back to the P2P coupling channel if the conversation again is restored to two participants (providing that the P2P coupling channel is still active when the conversation is restored to two participants).