This dissertation is a novel way of approaching Mariology since it presents an over-arching unity with Sacramentology, Christology, and Ecclesiology. It asserts intrepidly that the Blessed Virgin Mary is a sacrament of God’s saving grace. In the order of grace, Jesus is God’s primordial sacrament but Mary, in the order of time, became the first sacrament of the Trinity since she conceived in her womb the Son of God when the Holy Spirit overshadowed her by the power of the Most High (cf. Lk 1:31-35). The dissertation shows how Mary has an intrinsic relationship with the sacraments by placing her parallel with the different aspects of the sacraments according to the teachings by the Fathers of the Church and the magisterium. It is further posited that, just as the sacraments are sensible signs, Mary is the sign of the woman. If the sacraments have their origin in Christ, Mary is the mother of Christ, and if the sacraments give grace, Mary is full of Grace and a dispenser of Grace as well. It is claimed in this dissertation that there is a Marian dimension in the sacraments of Christian initiation of Baptism, Confirmation and Eucharist, in particular, and in all the seven ritual sacraments, in general.