Effie Louise Power (February 12, 1873 – October 8, 1969) was a children's librarian, educator, author, and storyteller. She encouraged children's book production and evaluated children's literature. She “directly influenced the development of services to children in three major United States cities: Cleveland, St. Louis, and Pittsburgh.” Power also traveled across the U.S. lecturing students and librarians on children and youth library services. She worked to build a network of children's librarians across the country who supported each other and established high standards for all in the profession.