A book that gives a profound explanation of how one can relate with the Immaculate by means of "the Marian Vow" of total consecration to the Immaculate that is transformative and life-changing. This book is a treatise on total consecration to the Immaculate, conceived initially by St. Maximilian M. Kolbe and has developed into the distinctive charism of the Franciscans of the Immaculate. Such charism finds its consummation in the profession of this Marian consecration in the form of a religious vow, known as, "The Marian Vow." Finding its original inspiration in St. Maximilian Kolbe who envisioned of a "fourth vow" of consecration that puts no limit to the missionary work of the religious, Fr. Stefano Manelli, the founder of the Franciscans of the Immaculate continued with the same inspiration and develop it to include both Marian and missionary character. This book is the theological and ascetical explanation of this Marian Vow. The book is not, by all means, exclusive to the Franciscans of the Immaculate. One can find universal insights based on solid spiritual theology of how one can relate in a more personal way with the Immaculate who ceases to be just a mere figure of veneration; she becomes alive and present to one's soul in a unique way that is transformative and life-changing. This book is utterly unique and inspired. As the Founder and Father General of the entire family of the Franciscans of the Immaculate (Friars, Sisters, Poor Clares, Tertiaries, and M.I.M.), Fr. Stefano has distilled, and put into writing for his children, the illumination he has received about the Marian Vow over the past decades. This work is the fruit of his life of prayer, study, and missionary activity. It is the fruit of his profound union with the Immaculate Heart of Mary.