A method for managing a target list on behalf of a user agent client (110, 210) for establishment of a communication session, the method comprising a server performing the steps of: receiving a request (140, 240) from the user agent client (110, 210), the request containing at least one uniform resource identifier identifying a resource and at least one of conditions and evaluation parameters; in response to receiving the request, providing a subscription request to an information owning enabler; receiving, from the information owning enabler, a notification containing evaluation information associated with a candidate uniform resource identifier set generated based on information in the subscription request; evaluating (146, 340), using at least one of the conditions and the evaluation parameters provided in the request (140, 240, 320) from the user agent client (110, 210, 310), the information associated with the candidate uniform resource identifier set to create a selected candidate uniform resource identifier set comprising candidates that match the at least one uniform resource identifier provided in the request (140, 240) from the user agent client; and notifying the user agent client of the selected candidate uniform resource identifier set; and the user agent client initiating and establishing a communication session with candidates from the selected candidate uniform resource identifier set; receiving, from the information owning enabler, an updated notification (260, 334) providing a modified candidate uniform resource identifier set; re-evaluating, using the evaluation parameters provided in the request (140, 240) from the user agent client (110, 210, 310), the modified candidate uniform resource identifier set containing updated evaluation information; and providing a delta selected candidate uniform resource identifier set to the user agent client (110, 210, 310), the delta selected candidate uniform resource identifier set showing only the difference between the selected candidate uniform resource identifier set and the results of the step of re-evaluating; and the user agent client adding a candidate to the ongoing communication session or removing a candidate from the ongoing communication session based on the delta selected candidate uniform resource identifier set. receiving a request (140, 240) from the user agent client (110, 210), the request containing at least one uniform resource identifier identifying a resource and at least one of conditions and evaluation parameters; in response to receiving the request, providing a subscription request to an information owning enabler; receiving, from the information owning enabler, a notification containing evaluation information associated with a candidate uniform resource identifier set generated based on information in the subscription request; evaluating (146, 340), using at least one of the conditions and the evaluation parameters provided in the request (140, 240, 320) from the user agent client (110, 210, 310), the information associated with the candidate uniform resource identifier set to create a selected candidate uniform resource identifier set comprising candidates that match the at least one uniform resource identifier provided in the request (140, 240) from the user agent client; and notifying the user agent client of the selected candidate uniform resource identifier set; and the user agent client initiating and establishing a communication session with candidates from the selected candidate uniform resource identifier set; receiving, from the information owning enabler, an updated notification (260, 334) providing a modified candidate uniform resource identifier set; re-evaluating, using the evaluation parameters provided in the request (140, 240) from the user agent client (110, 210, 310), the modified candidate uniform resource identifier set containing updated evaluation information; and providing a delta selected candidate uniform resource identifier set to the user agent client (110, 210, 310), the delta selected candidate uniform resource identifier set showing only the difference between the selected candidate uniform resource identifier set and the results of the step of re-evaluating; and the user agent client adding a candidate to the ongoing communication session or removing a candidate from the ongoing communication session based on the delta selected candidate uniform resource identifier set.