Una Voce

The Foederatio Internationalis Una Voce (Latin for "With One Voice"; from the Preface to the Roman Canon) is an international federation of Catholic lay organizations attached to the Tridentine Mass.

The Foederatio Internationalis Una Voce (or FIUV) was founded on December 19, 1964 in Paris by Georges Cerbelaud-Salagnac in order to promote the Tridentine mass from the Pre-Vatican II Missale Romanum (1962). The organization argues that while the Second Vatican Council had introduced vernacular liturgies, it did not actually forbid the Latin mass, and that regular weekday and Sunday masses in Latin should be maintained. The organization also seeks to promote Latin Gregorian Chant, sacred polyphony and sacred art. Unlike some of the other Catholic traditionalist organizations, Una Voce seeks to remain faithful to the Pope within the Roman Catholic Church, and asserts that the Tridentine and the vernacular masses should be allowed to co-exist. Among its prominent early members were the composers Maurice Duruflé and Oliver Messiaen.

A number of national associations developed during 1964 and 1965, and in 1966 an international association, the Foederatio Internationalis Una Voce was formed. It currently has over two dozen national affiliates.

FIUV members value the traditional Latin Mass as direct link with the early Church and for conveying the mystery and majesty of God, but have been critiqued for elitism and for its emphasis on private religious devotion. The group has been described as an "arch-conservative" organization by Episcopal Church organist James E Frazier. Traditionalist Catholics usually uphold orthodox Catholic moral teaching on abortion, contraception and marriage. However, members of the FIUV reject comparisons to fundamentalism.

FIUV was enthusiastic about the election of Joseph Cardinal Ratzinger as the Pope in 2005. Ratzinger had spoken at a conference, and had praised FIUV's role in supporting the use of the Roman Missal within the guidelines set out by the Vatican. The organization's influence at the highest levels of the Vatican has led to the authorization of the Tridentine Mass by local bishops in specific circumstances.