A method and a system is described for controlling a service in a service provisioning network. The method including the steps of: a serving network node associated with a user terminal receiving a registration message, the user terminal having one or more of services, preferably VoIP services; and, the serving network node retrieving in response to the registration message service routing information associated with the first user terminal, the service routing information being arranged to route service messages associated with the first user terminal via a stateless application server, the stateless application server being adapted to perform control actions on said service messages.