1. An integration services network for facilitating access to a composite service by a plurality of users having associated client machines, each of the users being associated with one of a plurality of independent enterprises, the network comprising: at least one data store having a directory stored therein which maps an identity for each of the users to a policy framework which defines access information relating to a plurality of services; and at least one computing device which is operable to set up the composite service by integrating operation of the plurality of services, the plurality of services being associated with and controlled by a plurality of independent service providers, the at least one computing device further being operable to connect with the client machines and each of the services, and to selectively facilitate interaction among the client machines and the services with reference to the directory and the policy framework, thereby enabling each of the users to access the plurality of services as an integrated solution.