Measures for enabling media bypass of one or more session border controllers (SBCs) in a telecommunications network which includes a plurality of SBCs. An SBC receives an inbound offer message requesting setup of a media session between an originating endpoint device and a terminating endpoint device. The SBC transmits an outbound offer message to an ensuing SBC, wherein the originating endpoint device address comprised in the inbound offer message is re-written with an SBC address in the outbound offer message. The SBC receives an inbound answer message including a terminating endpoint device address. In response to receipt of the inbound answer message, the SBC transmits an outbound answer message to the originating endpoint device without re-writing the terminating endpoint device address, whereby the SBC and the ensuing SBC are bypassed in the media path for the media session.