Best known for her design of the Union Theological Seminary Classification System, JULIA PETTEE was a master librarian. Her ideas about the organization of knowledge were philosophically grounded in a conviction about the unity of knowledge, growing out of her experience as a cataloger at Vassar College and Rochester Theological Seminary. Drawing on an article by psychologist Hugo Munsterberg in the Atlantic Monthly, she ingeniously structured the Union Classification System of 1911 to reflect his ideas about how exhibits should be arranged at the International Congress of Arts and Sciences held in St. Louis in 1904. During her thirty-year career as Head Cataloger at Union Theological Seminary in New York, she presided over the reclassification of 165,000 books. The system she designed came to be used in the libraries of more than fifty theological seminaries during the first half of the twentieth century. Through her many articles and books, her influence was widely felt in professional circles of the American Library Association."