A method of power control in a wireless communications system wherein blocks are transmitted from a transmitter to a receiver via a wireless transmission channel. The method comprises comparing a target signal quality value with a received signal quality value and providing the results of the comparing step to the transmitter to adjust transmit power based on the comparing step. The target signal quality value is set by the following steps: determining an initial target value; determining if received blocks have been successfully decoded; identifying the received blocks as pass or fail blocks; when pass blocks are received, comparing the target signal quality value with the received signal quality value and decreasing the target value only if the target value is greater than the received signal quality value less a margin.