The Board of the Music Encoding Initiative (MEI) is pleased to announce the availability of the MEI 4.0 Schema. The MEI is an international collaborative effort to capture the semantics of music notation documents as machine-readable data. For more information about MEI, please visit

This release comes after two years of extensive community consultation and development, and we thank all of the contributors in the community who have provided valuable input, feedback, critique, and development.

These conversations have resulted in the most collaborative music notation schema in history. Although there have been many music notation formats, few have achieved broad consultation and feedback, and even fewer have been co-developed in consultation with such a broad spectrum of stakeholders, from industry partners to librarians, publishers to researchers, and computer scientists to digital humanists. It is our sincere hope that we are able to grow and maintain these collaborations into the future.

Although we are releasing the schema today, there is still work to be done. Along with this release, we are seeking help from the community in updating the guidelines, documentation, tools, and tutorials.

The release of the schema represents the beginning of a transition period, where we will be asking contributors to help us write and expand our documentation, and make MEI more broadly accessible to newcomers and specialists. Over the next few months the technical team will be organizing documentation development “sprints” where we hope members of the community will help contribute content updated to the new specification.

The dates for these sprints will be announced on the MEI-L, and members of the technical team will be available on the MEI Slack channel for consultation and discussion during the sprints. It is our goal to present MEI 4.0, both schema and documentation, to the community at the 2019 Music Encoding Conference in Vienna.

For an overview of the changes in MEI 4.0, please see the Release Notes available on GitHub:

A detailed overview of the changes in the schema are available here: