If we try to increase the level of automation in Enterprise Application Integration (EAI) scenarios, we confront challenges related to the resolution of data heterogeneities, service discovery and process composition. In this paper, we propose the Enterprise Interoperability Ontology (ENIO) that provides a shared, common understanding of data, services and processes within enterprise application integration scenarios. ENIO consists of an Upper EAI ontology, which is based on the DOLCE-SUMO alignment, with extensions called facets that cover several dimensions of the EAI domain. Each facet contains a relative meta-model that utilizes widely adopted standards