The ecumenical movement, which received tremendous impetus from Vatican II, has shown signs of a slowdown at the beginning of the 21 ^st century. Although a survey of ecumenical literature reveals that the hallmarks of dialogic communication (openness, transparency and generativity) are still goals of the movement, there is evidence that the current impasse is at least partially the result of paying insufficient attention to two interrelated factors: epistemology and method. Adopting the epistemology of Bernard Lonergan as its conceptual framework, this study presents the thesis that typical comparative or “convergence” method, which so far has characterized most ecumenical dialogue, has not been sophisticated enough to uncover deep differences of epistemology between dialogue partners. The author proposes Lonergan's theological method, which is directed at the goal of self-transcendence, as an ideal tool for helping dialogue leaders to transcend the epistemological and doctrinal barriers of the past. As a case study, she examines the reports of the International Reformed-Catholic Dialogue (1968–2007) for signs of epistemological divergence, using content analysis to identify key words that are indicative of two different functional theories of knowing: knowledge by confrontation in the Reformed tradition, and knowledge by participation in the Roman Catholic tradition. The study ends with recommendations from Lonergan's method for superseding these epistemological differences, with a special focus on the role of epistemology in either facilitating or stalling ecumenical reception.