1. A system for providing data of a user stored on a data providing computer system to a data consolidating computer system, the system comprising: a matching system connection manager having an input/output coupled to the data consolidating computer system via a first communication facility, the matching system connection manager for setting up, via the first communication facility, a connection with the data consolidating computer system and validating the data consolidating computer system; a matching system setup manager at a matching computer system, the matching system setup manager having an input for receiving: from the data consolidating computer system from which an indication was previously received that the user had proved an association with one of a plurality of firms with which data consolidating computer system the user is able to prove an association and on which the user has a first user identifier, a second user identifier that also identifies the user on the data consolidating computer system, and that is different from the first user identifier of the user, and that cannot be used to log the user into the data consolidating computer system, over the first communication facility; and from the data providing computer system a third user identifier that identifies the user on the data providing computer system and that cannot be used to log the user into the data providing computer system on which the user has a fourth user identifier; and wherein the matching system setup manager for providing at an output the second user identifier, associated with the third user identifier; and a matching system data request manager at the matching computer system, the matching system data request manager having an input coupled to the matching system setup manager for receiving the second user identifier associated with the third user identifier, and coupled to the data consolidating computer system for receiving the second user identifier, the matching system data request manager for: checking a validity of the user corresponding to the second user identifier, and the firm with which the user had proved the association; and responsive to the checking: converting the second user identifier into the third user identifier of the user; and providing at an output the third user identifier by to the data providing computer system over a second communication facility coupled to the matching system data request manager that is verified by the data providing computer system; receiving via the matching system data request manager input data of the user from the data providing computer system over the second communication facility responsive to the third user identifier provided; and providing at the matching system data request manager output coupled to the data consolidating computer system the data of the user associated with the second user identifier.