Abstract : In this paper we propose an approach to manage access rights in a content management systems which relies on semantic web models and technologies. We present the AMO ontology which consists (1) in a set of classes and properties dedicated to the annotation of resources whose access should be controlled and (2) in a base of inference rules modeling the access management strategy to carry out. When applied to the annotations of the resources whose access should be controlled, these rules enable to manage access according to a given strategy. This modelisation is flexible, extendable and ensures the adaptability of the AMO ontology to any access management strategy. We illustrate the use of AMO on the documents of a collaborative website managed by the semantic wiki SweetWiki in the ANR ISICIL project. We show how to annotate documents with AMO, we explain which AMO inference rules can be applied and which semantic queries finally enable to control access to SweetWiki documents.