Reverend Fr. Thomas Berry C.P. is a Catholic priest of the Passionist order, cultural historian and ecotheologian .

Among advocates of deep ecology and "ecospirituality" he is famous for proposing that a deep understanding of the history and functioning of the evolving universe is a necessary inspiration and guide for our own effective functioning as individuals and as a species. He is considered a leader in the tradition of Teilhard de Chardin.