As the Wireless Sensor Networks (WSNs) continue to evolve, it becomes more and more important. Furthermore, no one can deny that Quality of Services (QoSs) is still one of the most important areas in this domain. In this paper, a system for guaranteeing WSN QoS is proposed. The idea of this system is to use the previous individual solutions such as clustering, data prioritization and data classification in addition to efficient techniques for network management. Simulation of this system is achieved using the Network Simulation package (NS2). Simulation results are given to demonstrate the effectiveness of the proposed system in terms of throughput, latency, lost packets and sensor power consumption.