Readers, particularly those in the English-speaking world, will be delighted to receive this new study of the thought of the fourteenth century mystic of the Low Countries, Jan van Ruusbroec, one of the titans of the mystical life. For Ruusbroec, renowned master of mystical literature, the mystery of the Trinity constitutes the foundation of the mystical life. In his tractates, trinitarian mysticism meets trinitarian theology to a striking degree. In this most welcome study, Lieve Uyttenhove presents a comprehensive systematic theological exploration of Ruusbroec's trinitarian mysticism and offers new insights into Ruusbroec's thought, arguing that Ruusbroec saw no essential difference between God's inner-trinitarian life of love and God's life of love in relation to humanity and that the source of God's flowing-out (inden uutvloeiene) and drawing-back (inden weder invloeyene) is the unity of the Holy Spirit. In her careful textual study, Uyttenhove also explores the much discussed issue of the relationship of Ruusbroec's thought to that of Plotinus, Augustine, Pseudo-Dionysius, Hadewijch, William of Saint Thierry, Richard of Saint Victor, Thomas Aquinas, Bonaventure, and Meister Eckhart. Here is also a rich and valuable resource for all those interested in reconnecting theology and mysticism.