QoS indicators are commonly used when selecting Web Services (WSs) between different providers. However, typical QoS parameters do not reflect the subjective 'performance' perceived by the end-users of the service, commonly called the Quality of Experience (QoE) of the service. In this paper, we describe a novel approach for using the QoE as a criterion for WS selection, including an analysis of the different influence factors affecting the perceived quality and a methodology for measuring QoE and establishing a correlation model between QoS/QoE. Furthermore, some real experiments with a set of end-users have been performed and interesting results illustrated.