Abstract: Instant messaging method and communication system for communicating between a first user at a first user terminal of the communication system and a second user at a second user terminal of the communication system. Instant messages are transmitted over the communication system in both directions between the first and second user terminals, wherein the instant messages constitute a conversation between the first and second users. Each instant message of the conversation is stored in a store at a server of the communication system, wherein the server is accessible from a third user terminal of the communication system such that the first user can retrieve, at the third user terminal, each instant message of the conversation from the store.