Assistant cataloger Miami University Library, 1927-1928. Bibliographer Scripps Foundation for Research in Population Problems, 1928-1940. Chief census library project Library of Congress, 1940-1941.
Assistant chief, central information div. O.S.S., 1941-1944; assistant director University of Chicago Library, 1944-1947. Assistant professor Graduate Library School, University of Chicago, 1947-1951, associate professor, 1951-1952.
Dean school library science Western Reserve U., Cleveland, 1952-1970, professor, dean emeritus, from 1972. Brazilian lecturer Institute Bibliography and Documentation, 1957. Visiting professor Graduate School Library Science, University Texas, Austin, 1970-1971, U. Arizona, summer 1973, U. Kentucky, summer 1974, University of Minnesota, spring 1977.
Lecturer seminar on library education Liverpool (England) Polytechnic, 1974, U. P.R., 1979. Member President’s Committee Employment of the Handicapped, 1969-1980, President’s Committee Library Research and Education. United States delegate United Nations Educational, Scientific and Cultural Organization International Conference, Paris., 1950, International Conference on Bibliographical Classification, Dorking, England, 1957.
Board educators United Educators, Inc. Director Center Documentation and Communication Research, Western Reserve U., 1960-1971.
Author: Foundations of the Public Library, 1949, Bibliographic Organization, (with Margaret E. Egan), 1951, Historians, Books, and Libraries, 1953, The Classified Catalog, (with Mechanical Engineering Egan), 1956, Libraries and the Organization of Knowledge, 1965, Documentation and the Organization of Knowledge, 1966, The Compleat Librarian, 1970, Sociological Foundations of Librarianship, 1971, Foundations of Education for Librarianship, 1972, Knowing Books and Men, 1973, Introduction to Library Science, 1976. Editor: American Documentation, 1953-1960, Western Reserve U. Press, 1954-1959, Documentation in Action, 1956, Information Systems in Documentation, 1957, Information Resources: A Challenge to American Science and Industry, 1958, Toward a Theory of Librarianship (Conrad H. Rawski), 1973. Editorial board: Journal Library History.
Associate editor: Library Quar, 1947-1952. Advisory editor, 1952-1955, Journal Cataloging and Classification, 1947-1957. Editor-in-chief: Wiley-Interscience texts in Documentation and Library Science, 1958-1981.
Editorial board: Library Sci, India. Board editors: United Educators, 1961-1974. Trustee Council National Library Assns.