Here is a unique contribution to modern Catholic literature. Leo Darroch presents in chronological order a factual history, fully referenced, of the work of the Foederatio Internationalis Una Voce, a movement of lay people formed after the sudden and insensitive enforcement of Novus Ordo Missae. It is the first fully documented account of the decades-long struggle for the preservation of the traditional rite of the Mass in the face of unrelenting opposition from the bishops of the Church.