The author delivered this doctorate lecture on the 7 of November 2012 at the Sophia University Institute. His research aimed at deepening the theoretical roots, historical developments, and social perspectives that inform the dialogue between Christianity and religions in pluralistic societies. The observations are from a Christian perspective, following the theological path pursued by the Catholic Church, with a specific focus on the insight, example and practice of Chiara Lubich and the Focolare Movement in its global development. In light of the distinctive methodological traits that distinguish Sophia University Institute, the study aimed to apply an interdisciplinary and trans-disciplinary method, between history, theology and sociology, in order to probe the relations between religions. This approach seemed especially suited to meet the complex challenge of understanding the religious fact in a pluralistic society, with simultaneous trajectories of secularization and of increasing presence of religions in the public agenda and in the public square.