In recent years a powerful grassroots movement has emerged calling for the papal definition of a fifth Marian dogma declaring the Blessed Virgin Mary to be Co-Redemptrix, Mediatrix of all graces, and Advocate. There has also been strong opposition to any such definition for various reasons. In The Truth about Mary, Peter Dillard clarifies this debate by providing a rigorous analysis of each thesis contained in the proposed dogma and determining whether a formal definition is appropriate at this time. The resulting theological and philosophical evaluation will be helpful to readers seeking a better understanding of what is at stake in a controversy that has far-reaching ramifications for the future of the Church. Peter S. Dillard is a professional philosopher, theologian, and writer living in Tucson, Arizona. He is the author of Heidegger and Philosophical Atheology, A Neo-Scholastic Critique (2008).