The present invention provides a presence system capable of monitoring state
information, communication capabilities, or a combination thereof derived from
a plurality of sources over any number of disparate networks. The state information
bears on the presence or availability of the user and may take many forms. The
communication capabilities relate to a potential method by which one can communicate
with the user. Based on a profile provided by the user, the presence system evaluates
the state information or communication capabilities from one or more sources to
create presence information, including a preferred method or a prioritized list
of methods by which to communicate with the user. The presence information is then
delivered to subscribers of the presence information.