Abstract. There exist different ways how to understand and use context information for RDF data. This paper summarizes these different ways and concentrates on the source information. It shows what can be achieved by knowing the source information and will present the RDF-Source related Storage System (RDF-S3). RDF-S3 is an application implementing one way to keep track of the source information for each stored RDF triple. On top of RDF-S3 we developed an extended version of easy RQL (eRQL) that makes use of the source information supported by RDF-S3. Therefore queries can be restricted to trusted sources and results can be viewed inside their RDF graph context.