The Liber Usualis is a must for any choir or schola member wanting to sing the Gregorian Chant of the Traditional Latin Mass. It has the complete Latin settings of Gregorian Chant for every Mass of the year (Sundays, Solemnities, Commons and Feasts). It also has the complete music for Nuptial Masses, Requiem Masses, Holy Week, and Ordination. Additionally it provides much of the Gregorian Chant to be sung in Latin for the Divine Office (Vespers, Compline, etc.), as well as many other traditional Latin chants and hymns (Litanies, Benediction, etc.) The preface of the Liber Usualis tells the interested choir member how to read and sing Gregorian Chant. This book is a must for any person wanting to sing for the Holy Sacrifice of the Mass.