1.1 Main purposes This European Prestandard describes a system of concepts to support the development, maintenance, comparison and implementation of terminology systems, which in turn support data classification, communication, storage and retrieval in Nursing Information Systems and Nursing Records. This European Prestandard includes a set of categorial structures that cover nursing diagnoses and nursing actions. Even though the Prestandard is centered on nursing needs, it may be used for domains with similar semantic properties, such as the subject field covered by ICIDH-2. The main uses foreseen for the system of concepts are to: - provide a language to highlight the structure and/or the taxonomy of a terminology system, i.e. the most relevant and systematic criteria used by developers to organise the terminology system. This description may be used to harmonise a terminology system within the environment of an information system, e.g. by comparing information models and terminology models. - provide the criteria to generate systematic names from rubrics and terms of a terminology system, as a supporting feature to be distributed in the near future together with the usual presentation of the terminology system itself.