This research explores the origins, manifestations, and handling of theological dissent in the Roman Catholic Church in the decades since the Second Vatican Council (1962-1965). An examination of the Conciliar period identifies emerging antinomies, and explores the divergent hermeneutics of continuity and discontinuity which stimulated and contextualised post-Conciliar dissent. The relevance of Karl Rahner’s theological anthropology and his perspectives on the dignity and freedom of the human person are considered, including his prescient views on the role, characteristics and mission of an emerging world Church. Efforts by the Roman magisterium to control and suppress dissent, independent theological exploration, and challenges to its authority, are examined, with detailed focus on particular theologians and episodes of dissent and censure, relating to sexual ethics, and to feminist theology and the role of women in the Church. The role and activities of the Congregation for the Doctrine of the Faith (renamed in 2022 to Dicastery for the Doctrine of the Faith) as guardian and arbiter of orthodoxy is explored through a detailed examination of its documentary record. Its theological preoccupations and its disciplinary activities under successive papacies are examined and evaluated. The current possibilities, stimulated by Pope Francis’ synodal project, for a dialogical approach to dissent, emphasising discernment and principles of participation and co-responsibility, are explored. The treatment, within the synodal process, of unsettled questions, a growing diversity of theological expression, and particular neuralgic topics on which dissent continues to be focused, is examined. The 2023 Synod Assembly’s Synthesis Report, and its reception thus far, are analysed and critiqued. Conservative dissent and opposition to the possibility of transposing the hitherto adversarial context of dissent into a more constructive, and collaborative frame, as the synodal process unfolds, is examined. Future trajectories for dissent, proposed as a necessary, ineradicable and constitutive reality in the Church, are discussed.