Abstract
The Object Role Modelling (ORM2) is a conceptual modelling approach combining both textual specifications and graphical language, similar to UML and ER, and adopted by Visual Studio, the integrated development environment designed by Microsoft. This paper introduces a new linear syntax andcorresponding complete set-theoretic semantics for a generalization of ORM2
language. A core fragment of ORM2 is defined, for which a provably correct encoding into ALCQI description logic is presented. Based on these results, an extensive and systematic critique of alternative approaches to the formalisation of ORM2 in (description) logics published so far is provided. A first prototype has been implemented, which offers a back-end for the automated support of consistency and entailment checks for ORM2 conceptual schemas along with its translation into ALCQI knowledge bases.