 Throughout her career, Patricia Monaghan's work dealt with issues of spirituality, especially women's spirituality.In 1979, she published the first encyclopedia of female divinities, a book which has remained steadily in print since then and was eventually republished in a two volume set as "The Encyclopedia of Goddesses and Heroines".She also published an encyclopedia of Celtic myth, "The Encyclopedia of Celtic Myth and Folklore", and edited a three-volume collection of essays entitled "Goddesses in World Culture", published in 2010 by ABC-CLIO.