A persistent personal messaging system provides tuple space functionality supporting a user changing between a plurality of client devices, even within a loosely coupled, distributed system for persistent personal messaging. A user, irrespective of which messaging client they are using, logs on to the system. The act of logging on places a tuple, representing the user, into the tuple space. A “contacts” service agent finds the friends and groups that the user belongs to and notifies other users that the user has logged on. Given the on-line status of other users and groups, a “history” service agent will retrieve previous messages from the tuple space that formed the user's conversations with users and groups, as if the user had never logged off or switched devices. When the user adds a new message to any conversation, the message is added as a tuple to the tuple space.