- All SNOMED CT editions (except the International Edition) are a combination of one or more extension modules, together with the modules from the SNOMED CT International Edition.
- A complete SNOMED CT edition may be prepared and released by SNOMED International or by the provider of a SNOMED CT Extension. Alternatively, a SNOMED CT Edition may be derived from one or more release packages, by combining the contents of an identified focus module with the contents of the relevant version of all modules on which the focus module depends.
- The dependencies between modules are represented using the |Module dependency reference set (foundation metadata concept)|.
- A SNOMED CT Edition can be identified using a URI as specified by the URI Standard (2.1 URIs for Editions and Versions).
- The SNOMED CT International Edition consists of the focus module, |SNOMED CT core module|, and the module on which it depends, |SNOMED CT model component module|
- The US National Edition (including the US SNOMED to ICD-10-CM maps) consists of the focus module, |SNOMED CT to ICD-10-CM rule-based mapping module|, and the three modules on which this depends, |US National Library of Medicine maintained module|, |SNOMED CT core module| and |SNOMED CT model component module|.