This short book presents the teaching of Mary the Co-Redemptrix, describing her role, united with Christ but subject to Him, in the Redemption. The term today is surrounded by great confusion and on account of this, there exists a poor understanding of Our Lady. Not only is the subject of Co-Redemption not understood, but a vital aspect of Mary's life and vocation as Mother of God and of the Church is missed. In order to clarify this doctrine and bring others to a deep relationship with the Mother of the Church, the author explains the term, and turns to the saints from the Church's history to demonstrate the constant teaching of Co-Redemption. At the close of the work a series of topical and theological objections are presented and answered.