This ÖNORM specifies the fundamental characteristics of the information model to be implemented by a specific architectural layer (i.e. the middleware) of the information system to provide a comprehensive and integrated storage of the common enterprise data and to support the fundamental business processes of the healthcare Organization, as defined in Part 1 of ÖNORM EN 12967-1. This specification does not aim at representing a fixed, complete, specification of all possible data that may be necessary for any requirement of any healthcare enterprise. It specifies only a set of characteristics - in terms of overall Organization and individual information objects - identified as fundamental and common to all healthcare Organizations, and that shall be satisfied by the information model implemented by the middleware. Preserving the consistency with the provisions of this standard, physical implementations shall allow extensions to the standard information model in order to support additional and local requirements. Extensions shall include both the definition of additional attributes in the objects of the standard model, and the implementation of entirely new objects. Also this standard specification shall be extensible over time according to the evolution of the applicable standardisation initiatives.