During the last years, Web Information Systems have evolved from simple information sources to systems offering services to end-users. The development of this kind of systems presents different challenges, such as the alignment between business services and their implementation, and the way business processes are placed in the system. To address this type of challenges this paper presents a methodological and technical proposal for Service-Oriented development of Web Information Systems. It follows a model-driven approach, defining a set of models at different levels of abstraction and the model transformations needed to connect them. Besides, the development of a conference management system is used as case study to illustrate the proposal.