 Bartholomew's tenure has been characterized by intra-Orthodox cooperation, intra-Christian and inter-religious dialogue, and formal visits to Roman Catholic, Old Catholic, Orthodox and Muslim leaders seldom previously visited by an ecumenical patriarch.He has exchanged numerous invitations with church and state dignitaries.His efforts to promote religious freedom and human rights, his initiatives to advance religious tolerance among the world's religions, as well as his efforts to promote ecology and the protection of the environment, have been widely noted, and these endeavors have earned him the title "The Green Patriarch".