This essay explores moral decision-making, moral witness/advocacy, and moral teaching/formation, framed in terms of receptive ecumenism as a mandate for Christians to live out the faith together in visible witness. The context is the bilateral and multilateral ecumenical dialogues, of which the recent U.S. Anglican-Roman Catholic dialogue document, Ecclesiology and Moral Discernment, is an exemplar. Global, regional, and local examples of current ecumenical efforts around ethical decision-making, advocacy, and action are provided in each of the three areas. Eight challenges to the work of ecumenical dialogue on moral matters are identified. Finally, six characteristics of morally serious ecumenical communities are described.