A method, performed by a networked slave device (203A, 203B, 203C, 203D), for synchronizing a local clock with respect to a master clock of a master device, the method being characterized in: (a) providing a group of probe frames to the master device, thereby to receive responses in respect of at least a selection of these probe frames, wherein each response includes data for allowing determination of an estimated clock offset, the data for allowing determination of the estimated clock offset including: (i) a probe frame transmission timestamp taken with respect to the slave device's clock; (ii) a probe frame receiving timestamp taken with respect to the master device's clock; (iii) a response transmission timestamp taken with respect to the master device's clock; and (iv) a response receiving timestamp taken with respect to the slave device's clock; (b) filtering the responses, thereby to identify a best response for the group of probe frames, wherein the best response is defined to be a response with a minimum round-trip time value and wherein all responses with a RTT value greater than a predefined threshold value are discarded, the predefined threshold value derived using the minimum RTT value; (c) repeating steps (a) and (b) for successive groups of probe frames thereby to identify a respective best response for each of the successive groups of probe frames; (d) selectively calculating estimated clock offset values based on the best response in respect of each group of probe frames, thereby to determine a relative clock offset drift; and (e) repeatedly adjusting the local clock based on calculations of the relative clock offset drift. (a) providing a group of probe frames to the master device, thereby to receive responses in respect of at least a selection of these probe frames, wherein each response includes data for allowing determination of an estimated clock offset, the data for allowing determination of the estimated clock offset including: (i) a probe frame transmission timestamp taken with respect to the slave device's clock; (ii) a probe frame receiving timestamp taken with respect to the master device's clock; (iii) a response transmission timestamp taken with respect to the master device's clock; and (iv) a response receiving timestamp taken with respect to the slave device's clock; (i) a probe frame transmission timestamp taken with respect to the slave device's clock; (ii) a probe frame receiving timestamp taken with respect to the master device's clock; (iii) a response transmission timestamp taken with respect to the master device's clock; and (iv) a response receiving timestamp taken with respect to the slave device's clock; (b) filtering the responses, thereby to identify a best response for the group of probe frames, wherein the best response is defined to be a response with a minimum round-trip time value and wherein all responses with a RTT value greater than a predefined threshold value are discarded, the predefined threshold value derived using the minimum RTT value; (c) repeating steps (a) and (b) for successive groups of probe frames thereby to identify a respective best response for each of the successive groups of probe frames; (d) selectively calculating estimated clock offset values based on the best response in respect of each group of probe frames, thereby to determine a relative clock offset drift; and (e) repeatedly adjusting the local clock based on calculations of the relative clock offset drift.