1. A method of charging in a communications network in which a plurality of charging and enforcement (CaE) components operate as enforcement points for a single data communication, comprising: receiving, from a first CaE component, one or more usage records related to enforcement of the single data communication by the first CaE component; receiving, from a second CaE component, one or more usage records related to enforcement of the single data communication by the second CaE component; generating correlated usage records related to enforcement of the single data communication by the first CaE component and the second CaE component by using a common Service Data Flow (SDF) to correlate the one or more usage records received from the first CaE component with the one or more usage records received from the second CaE component; and using the correlated usage records related to enforcement of the single data communication to determine a charge value that identifies correct charges to be applied for the single data communication.