Giacinto (Hyacinth) D'Urso (1913-2002), Dominican friar of the Province of San Marco and Sardegna (later the Roman Province), is regarded by many Italian commentators as the foremost expert on the mysticism of Catherine of Siena. After his ordination in 1936 he obtained a doctorate in theology from the Angelicum in Rome. He served the Order in various capacities as novice master, prior, pastor, preacher and, for a time, professor of theology at the Angelicum. For many years he was the editor of the acclaimed Dominican spirituality journal Rivista di Ascetica e Mistica and was a lifelong...