The Gregorio project offers a complete suite of GPLv3-licensed tools for typesetting Gregorian chant scores. The system centers on gabc, a plain-text notation system that represents chant melodies using ASCII characters, paired with GregorioTeX, a specialized TeX style for rendering musical scores. Together with conversion software that transforms gabc files into GregorioTeX output, these tools enable musicians and publishers to produce professional-quality chant notation.

The project emerged from the need for accessible, open-source solutions in sacred music publishing. By building on the widely-used TeX typesetting system, Gregorio provides a powerful alternative to proprietary music engraving software. The plain-text nature of gabc allows chant manuscripts to be stored, shared, and version-controlled like any other text document, while maintaining the aesthetic quality expected in liturgical publications.

Users can access comprehensive documentation and tutorials for version 4.0 and later through the project's website, with historical information preserved in GitHub repositories. The 100% free software approach ensures that religious communities, scholars, and publishers can produce chant materials without licensing restrictions. The project's name derives from the invented Latin verb "gregoriare," meaning "to sing Gregorian chant," reflecting its focus on authentic liturgical music notation.