A method is disclosed for use in device-to-device (D2D) discovery in a wireless communication network. The network includes at least one base station and a plurality of D2D capable user equipments (D2D-UEs). The network also supports cellular communication and direct communication between D2D-UEs. The method includes transmitting D2D discovery system information (D2D-SIB) from the base station to D2D-UEs, wherein the D2D-SIB indicates frame(s)/subframe(s) for D2D-UEs to transmit D2D discovery request signal(s) and frame(s)/subframe(s) for D2D-UEs to transmit D2D discovery response signal(s). The method also includes transmitting one or more D2D discovery request signal(s) from one D2D-UE, and upon receipt of a said D2D discovery request signal by another D2D-UE, transmitting from said other D2D-UE one or more D2D discovery response signal(s). The D2D discovery request signal(s) and D2D discovery response signal(s) are transmitted on the frame(s)/subframe(s) indicated in the D2D-SIB.