A system comprising: a control device for controlling an amount of power provided to an electrical load, wherein the control device is one of a control-source device or a control-target device included in a plurality of control devices, the control device comprising: a wireless communication circuit configured to send and receive digital messages; and a control circuit communicatively coupled to the wireless communication circuit, the control circuit configured to: receive a broadcast discovery message transmitted by a load control discovery device ; determine a received signal strength (RSSI) at which the broadcast discovery message is received; determine that the received signal strength is above a predetermined signal strength threshold; and when the signal strength at which the broadcast discovery message is received is above the predetermined signal strength threshold, send, via the wireless communication circuit, a response message, wherein the response message is configured to report receipt of the broadcast discovery message, and wherein the response message includes a device identifier of the control device and the received signal strength (RSSI) of the broadcast discovery message; characterised in that said control circuit is configured to perform above steps responsive to receipt of a discovery trigger message from a system controller and subsequent entry of the control device into a discovery mode. a wireless communication circuit configured to send and receive digital messages; and a control circuit communicatively coupled to the wireless communication circuit, the control circuit configured to: receive a broadcast discovery message transmitted by a load control discovery device ; determine a received signal strength (RSSI) at which the broadcast discovery message is received; determine that the received signal strength is above a predetermined signal strength threshold; and when the signal strength at which the broadcast discovery message is received is above the predetermined signal strength threshold, send, via the wireless communication circuit, a response message, wherein the response message is configured to report receipt of the broadcast discovery message, and wherein the response message includes a device identifier of the control device and the received signal strength (RSSI) of the broadcast discovery message; characterised in that said control circuit is configured to perform above steps responsive to receipt of a discovery trigger message from a system controller and subsequent entry of the control device into a discovery mode. receive a broadcast discovery message transmitted by a load control discovery device ; determine a received signal strength (RSSI) at which the broadcast discovery message is received; determine that the received signal strength is above a predetermined signal strength threshold; and when the signal strength at which the broadcast discovery message is received is above the predetermined signal strength threshold, send, via the wireless communication circuit, a response message, wherein the response message is configured to report receipt of the broadcast discovery message, and wherein the response message includes a device identifier of the control device and the received signal strength (RSSI) of the broadcast discovery message; characterised in that said control circuit is configured to perform above steps responsive to receipt of a discovery trigger message from a system controller and subsequent entry of the control device into a discovery mode. <EOS>