# Introduction to Editorial Guide **This Editorial Guide is used for Education Purposes Only. It is used in the Authoring Courses and Certifications. It is based on the January 2026 Editorial Guide.** ## Background SNOMED CT is a comprehensive, international, logic-based reference terminology designed to represent clinically relevant information in a consistent, computable way. Originating from the union of NHS Clinical Terms Version 3 and SNOMED RT, it has evolved to support contemporary clinical practice and technological advances . The Editorial Guide exists to support the ongoing development and quality assurance of this terminology, ensuring content is modeled consistently and in alignment with best practices. Content development is provided by expert clinicians driven by the requirements of user communities. This includes core content for use internationally and content relevant to national extensions for local implementation. Its logic-based definitions represent terminological knowledge, or what is always true about the meaning of concepts. It consists of codes, that correspond to concepts, arranged in a polyhierarchical manner, as well as relationships between the concepts, which further define the meaning. *Description logic (DL)* is the formal foundation of meaning in SNOMED CT. The way that concepts have been modeled in SNOMED CT permits them to be represented using description logic. A DL *reasoner* is used to classify SNOMED CT. The DL reasoner also helps test expressions for subsumption and equivalence. ## Purpose The SNOMED CT Editorial Guide provides the rules, conventions, and principles required to model SNOMED CT concepts. It serves as the definitive reference for authoring and maintaining content in the International Release, while also supporting extension creators . The guide ensures that terminology is reliable, unambiguous, and interoperable for healthcare applications. ## Scope This guide covers the editorial policies for precoordinated content, meaning concepts and rules applicable to all precoordinated SNOMED CT content. Rules specific only to postcoordinated content are not included; these are managed separately through the MRCM ([Machine Readable Concept Model](https://browser.ihtsdotools.org/mrcm)) browser . It also provides information on concept modeling, naming conventions, inactivation, attributes, and rules for specific hierarchies. Text that is protected by copyright will not be accepted for inclusion unless accompanied by a release from the copyright holder. ## Audience The primary audience of the Editorial Guide is SNOMED International editors responsible for maintaining the International Release. However, it is also relevant for extension developers, implementers, and others involved in clinical terminology management . For national or local extensions, the [Extensions Practical Guide](https://app.gitbook.com/o/h8Z6qGxuQrzM9vbx5bPT/s/3RKZIWpWFT0ocCgNT16E/) offers complementary guidance. ## Review Cycle The Editorial Guide is a living document that is continually revised. The [Summary of changes](https://docs.google.com/spreadsheets/d/1xHZNeNQwkCcUPaZGEl28GFGv_WMTHZoeHeAV5cSjOFU/) spreadsheet records changes via monthly tabs. ## Contact and Feedback The Editorial Guide is maintained by SNOMED International, the organization responsible for the ongoing development and distribution of SNOMED CT. Users are encouraged to provide feedback or seek clarification by contacting SNOMED International at . Additional resources, licensing details, and membership information are available at [www.snomed.org](http://www.snomed.org). Provide Feedback --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.snomed.org/education/snomed-ct-education-editorial-guide/readme/introduction-to-the-snomed-ct-editorial-guide.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.