The quality of service (QoS) allocation in a distributed environment has been an area of focus in recent work on multimedia systems and networks. This paper provides a decentralized approach to allocate QoS through a market. In our approach, each agent makes decisions according to its local knowledge and interests that change dynamically, and prices adjust to clear the market in each resource. The market prices reflect system-wide values, inducing agents to produce and consume appropriate amounts of the various resources. We describe a market model for allocating bandwidth in an actual networked meeting environment called FreeWalk. Experiments reveal the effectiveness of the market-based approach to allocating QoS for multimedia network applications.