In order to address the problem of allowing a GGSN of a UMTS core network to work towards multiple Policy Control Functions (PCFs) co-located with P-CSCF nodes using the COPS protocol, a policy control function coordinator (PCF-C) is implemented between the GGSN and the P-CSCF. A single COPS connection is established between the GGSN and the PCF-C while a COPS connection is established between the PCF-C and each of the P-CSCF nodes. Decisions made at the PCFs are routed to the GGSN via the PCF-C, and responses generated at the GGSN are routed to the appropriate PCFs via the GGSN. This architecture avoids conflicts which might otherwise arise with the COPS protocol.