<span lang="en">This chapter introduces the principal characteristics of MANETs and shows how these particularities may affect both QoS conditions and QoS management/provisioning systems, and therefore the capabilities of MANETs for properly providing multimedia services. After a deep analysis of different QoS mechanisms at different layers, the authors claim that QoS management cannot be handled only at the network layer or by applying some QoS-aware routing protocols. In fact, any end-to-end QoS provision architecture will demand QoS control mechanisms and information exchange among all the layers. A clear understanding of different proposals aimed at coping with QoS requirements at different layers will not only provide researchers with valuable information for designing better multimedia capable MANETs, but will also assist them in evaluating the need for a unified cross-layer approach in order to optimize the performance of analyzed protocols.</span>