Abstract
IT Infrastructure Library (ITIL) has become the de facto standard for IT Service Management (ITSM). Despite the advantages in the adoption of ITIL’s best practices, some problems have been identified: different interpretations due to the complexity of concepts with poor specification and formalization; different approaches to the same problems; difficulties exchanging process models in different process model languages. Besides all published work, is still missing a metamodel expressing the core concepts, their relationship, and constraints. In this paper, we propose an ITIL metamodel to reduce conceptual and terminological ambiguity, addressing the identified problems, namely: (1) describing the core concepts of ITIL to be used by other approaches; (2) allowing the integration, exchange, sharing and reutilization of models; and (3) the use of different modelling languages following the defined principles.