Simultaneous support of multiple video streaming sessions over a shared wireless network requires careful resource allocation to achieve high utilization while dynamically adapting to network and video fluctuations. We propose a distributed algorithm for channel time allocation among multiple video streams, and investigate several heuristic packet pruning schemes for rate adaptation of highdefinition (HD) video streams. Simulation results are presented for streaming multiple HD video sequences over an 802.11a network. In comparison with TCP-Friendly Rate Control (TFRC) and a basic scheme without rate adaptation, it is shown that the proposed scheme can sustain higher video quality with lower packet delivery delay.