Abstract
In Ontology-Based Data Access (OBDA), the aim is to use an ontology to mediate the access to data sources. We present a plug-in for the standard ontology editor Protégé that allows users to model ontologies with mappings to data sources in order to perform OBDA. We argue that our plug-in, together with an OBDA-Enabled reasoner, allows users to build, test, and deploy OBDA Systems in academic or industrial settings.