The latest full release (MEI 2013 = v.2.1.1) is available from https://github.com/music-encoding/music-encoding/archive/MEI2013_v2.1.1.zip. This file contains the MEI Guidelines, RelaxNG schemata, customizations, and source files for the MEI specifications and guidelines in a single package.
The latest schemata for validating MEI instances are also available individually. These files contain constraints expressed in Schematron. The use of XML editors and other processes capable of following these additional rules is highly recommended.
- mei-CMN.rng — supports Common Western Music Notation and deactivates other repertoires.
- mei-Mensural.rng — supports only Mensural notation.
- mei-Neumes.rng — supports only Neume notation.
- mei-all.rng — allows all repertoires at the same time. Use only if you need to support multiple repertoires in the same file.
- mei-all_anyStart.rng — allows any element to be the topmost element in an MEI instance. Useful for validating MEI fragments.
The documentation of the latest release, containing documentation of the modular structure of MEI, usage guidelines, and best practices recommendations, is also available as a separate PDF (6.48 MB).

