This book is essential for anyone who wishes to learn Gregorian Chant. Few words are necessary to introduce the present work to English speaking students of plainsong. Such a handbook has long been needed and is sure of its welcome. Neither the well known Stan brook Grammar of Plainsong nor Madame Ward's valuable school courses cover so much ground as Dom Gregory Sunol in his Spanish "Metoda". The book first appeared in 1905, prefaced by a commendatory letter from Dom Andre Mocquereau, the famous director of the Solesmes School. Its author has many years of teaching experience behind him, as well as sound theoretical knowledge of his subject. His work has proved its popularity and practical usefulness by going through a number of editions in the original Spanish, besides being translated into French and German. Indeed by compressing the Solesmes teaching within the narrow limits of a general text book Dom Sunol has rendered good service to the Gregorian cause. Not everyone has access to the monumental publications of Solesmes, the Monographies gregoriennes or the Paleographie Musicale, and countless students will be glad to find the subject matter of this latter work, especially the important seventh volume on Gregorian Rhythm, here summed up and analysed, while the extensive quotations from Dom Mocquereau's Nombre Musical gregorien, with which the Spanish author has enriched his later editions, will make them desirous of seeing this fascinating synthesis of the whole subject brought out in English. The French translation of Dom Suf'lol's work was made by Dom Maur Sablayrolles who tells us in his preface that he inserted a few additional chapters and altered and developed his original here and there in inconsiderable ways, always with the author's permission. The present English version is a faithful rendering of the sixth French edition, and except for some extension of the note on Latin pronunciation, now embodied in the text, nothing of any importance has been added. But the work has been prepared under the direct supervision of the Solesmes Benedictine Fathers at Quarr Abbey who have supplied invaluable help on almost every page, mainly in the direction of ensuring greater accuracy, clearing up obscure- passages, simplifying technical points and generally making the book more accessible to the ordinary student of plainsong. The Spanish handbook was placed under the patronage of our Lady of Montserrat. In its English dress it is offered to our Lady of Quarr with the prayer that she may everywhere bless the work of those who are teaching the Catholic world to sing the praises of her Divine Son.