The main purpose of this European Standard is to support the safe transfer of the majority of hierarchical healthcare classification systems between organisations and dissimilar software products. It is intended to serve as the core representation, from which all publication forms can be derived. The Standard shall therefore be in depth enough to uniquely identify and describe the structure and the relevant elements in those systems. This Standard does not intend to prescribe the meaning of structuring elements in classification systems. This Standard is not meant to be a direct format for printing or viewing the contents of a classification system. Views and prints shall be derived from this representation by post processing.