Abstract: A method of performing an information transformation (T1-T4) within a communications network is provided. The information transformation (T1-T4) has one or more information objects (OA-OE, O1-O5) as inputs and the method includes providing in or associated with an output of said information transformation, tracking information that uniquely identifies all inputs to the transformation. Also provided is a system for locating a copy of a required information object within a communications network. The system records the location of copies of required information objects (OA-OE, O1-O5) within the communications network (1) and provides information referring to a network location of at least one copy upon request. A unique identifier of the required information object is used to verify the integrity of the information object.