A system and method which improve the performance of a wireless transmission system by intelligent use of the control of the flow of data between a radio network controller (RNC) and a Node B. The system monitors certain criteria and, if necessary, adaptively increases or decreases the data flow between the RNC and the Node B. This improves the performance of the transmission system by allowing retransmitted data, signaling procedures and other data to be successfully received at a faster rate, by minimizing the amount of data buffered in the Node B. Flow control is exerted to reduce buffering in the Node B upon degradation of channel qualities, and prior to a High Speed Downlink Shared Channel (HS-DSCH) handover.