Gerrit Cornelis Berkouwer (1903-1996) was a great master of dogmatic and ecumenical theology. He was a Reformed Protestant thinker, with roots in Dutch neo-Calvinism, a holder of the Chair in Dogmatics (1945-1974) at the Free University, Amsterdam, a position previously held by his two illustrious neo-Calvinist predecessors, Abraham Kuyper (1837-1920) and Herman Bavinck (1854-1921). Echeverria provides a much needed in-depth analysis and critique of his theology, particularly his evolving relationship with Catholicism in light of Vatican II. His contention is that Berkouwer’s careful and nuanced examination of Catholic theology—as well as possible responses to his critiques—offers important clues for the contemporary ecumenical project.