To personalize a service is to adapt its functionality and presentation according to the preferences of the user. Although personalization is becoming a natural requirement of future services, its realization is still facing quite a lot of challenges. Indeed, it is not simple to personalize services for a mobile user that is changing of devices, networks and domains. The information or data necessary for the personalization is quite often fragmented across different domains where interchanges are not allowed. This paper proposes to use the Service-Oriented Architecture as fundament for realizing personalization. It starts with the specification of the information space for personalization. It will study how this information space can be decomposed and distributed.