A method of facilitating P-CSCF restoration when a P-CSCF failure has occurred is disclosed. The method comprises a Proxy Call Session Control Function, ‘P-CSCF’ receiving a Session Initiation Protocol, ‘SIP’, message when said P-CSCF has been selected as a alternative P-CSCF to a failed P-CSCF and providing to an associated Policy and Charging Rules Function, ‘PCRF’, a message comprising to indication that P-CSCF restoration is required.