Users' concerns regarding their privacy have a negative impact on their confidence into e-services, and tend to slow down the widespread adoption of online services. Until today, the protection of personal data is mainly left to the legislation by means of guidelines. This paper aims to increase the perceived control by users over their data and to bring down into the technological reality the legislative data protection principles. To do so, it discusses the main concepts involved in the legislative privacy principles, and deduces a privacy semantic information model, i.e. a privacy ontology. This model serves to build users' privacy preferences and SP's privacy policies