Four years before the Solemn Definition of the Dogma of the Immaculate Conception in 1854, Dom Guéranger published his monumental work, Mémoire sur la Question de l’Immaculée Conception de la Très Sainte Vierge. With characteristic zeal and his outstanding sensus Ecclesiæ, he wished to share an enthusiasm and conviction which had been his since his seminary days. This first ever English translation of the work is published as a collaboration between the Benedictine nuns of St Cecilia’s Abbey, Ryde, and the monks of St Michael’s Abbey, Farnborough, to mark both the 150th anniversary of the solemn proclamation of the dogma and the bi-centenary of the birth of Dom Guéranger.