Method for an enhanced control function selection in a communication network and with respect to a user equipment requesting an IP (Internet Protocol) multimedia subsystem communication service from the communication network, wherein the communication network comprises an access network and a core network, the access network comprising at least one access node, wherein the communication network comprises a home subscriber server, a plurality of interrogating call state control function entities and a plurality of serving call state control function entities, wherein - with respect to the user equipment requesting the IP multimedia subsystem communication service being related to a service identity that is known to the home subscriber server - a specific interrogating call state control function entity is used among the plurality of interrogating call state control function entities, and a specific serving call state control function entity needs to be selected among the plurality of serving call state control function entities, wherein the method comprises the following steps: -- in a first step, upon a request of an IP (Internet Protocol) multimedia subsystem communication service by the user equipment, an initiating message, related to the service identity, is received by the specific interrogating call state control function entity, -- in a second step, subsequent to the first step, a location information request message is transmitted, by the specific interrogating call state control function entity, to the home subscriber server, -- in a third step, subsequent to the second step, a location information answer message is transmitted, by the home subscriber server, to the specific interrogating call state control function entity, wherein the location information answer message comprises a required capability information, the required capability information corresponding to a capability that needs to be provided by the specific serving call state control function entity that is to be selected, by the specific interrogating call state control function entity, among the plurality of serving call state control function entities, wherein any subsequent location information answer message - in response to a subsequent location information request message - that is -- received by the home subscriber server and -- transmitted either by the specific interrogating call state control function entity or by another one of the plurality of interrogating call state control function entities - as the requesting entity - and -- related to the service identity related to the IP multimedia subsystem communication service requested by the user equipment, likewise comprises a required capability information such that the requesting entity - the specific interrogating call state control function entity or the other one of the plurality of interrogating call state control function entities - selects the specific serving call state control function entity, that is thereby becoming the selected serving call state control function entity corresponding to the subsequent location information request message. -- in a first step, upon a request of an IP (Internet Protocol) multimedia subsystem communication service by the user equipment, an initiating message, related to the service identity, is received by the specific interrogating call state control function entity, -- in a second step, subsequent to the first step, a location information request message is transmitted, by the specific interrogating call state control function entity, to the home subscriber server, -- in a third step, subsequent to the second step, a location information answer message is transmitted, by the home subscriber server, to the specific interrogating call state control function entity, -- received by the home subscriber server and -- transmitted either by the specific interrogating call state control function entity or by another one of the plurality of interrogating call state control function entities - as the requesting entity - and -- related to the service identity related to the IP multimedia subsystem communication service requested by the user equipment,