Abstract— Modern day wireless networks are increasingly supporting various civilian applications that require high bandwidth for successful operation. In such cases, it is important to ensure proper maintenance of links that contribute the most to achieving the required level of service. In this paper, we1 devise a method to analytically characterize the importance of each link in a multichannel, multi-radio, multi-rate wireless mesh network in satisfying Quality-of-Service (QoS) requirements of active flows. We propose link importance metrics that can guide network/traffic engineers in properly provisioning the network to handle failures of critical links that contribute significantly to the achievability of flow demands. We consider single-commodity flows and perform simulations to evaluate the quality of our metrics. Keywords- QoS Provisioning, Link Importance, FussellVesely Measure, Birnbaum Measure