Annual reports filed with the State of Illinois pursuant to the 1891 Illinois legislative act to encourage public libraries in the state. From the founding of the Newberry Library in 1887 under the authority of the trustees of the Walter L. Newberry estate to its incorporation as a free public library, April 25, 1892, the Trustees' annual reports were titled, "Proceedings of the Trustees of the Newberry Library." After that date, the reports were titled, "Report of the Trustees of the Newberry Library." Reports in this form ceased in 1941.

Reports provide an annual summary of the Library's activities and financial condition. Included are reports of Trustee presidents Eliphalet W. Blatchford (1887-1913), Edward L. Ryerson, (1914-1928), Horace S. Oakley (1928 1929), and Alfred E. Hamill (1929-1941); reports of librarians William F. Poole (1887-1894), John Vance Cheney, 1894 1909, W. N. C. Carlton (1909-1920), and George B. Utley (1920 1941); financial statements; trustee, donor, and library staff lists; and statistics of library usage. Index for the years 1887-1933 available in the Library.

From 1942 to 1961 there were no annual reports issued by the Library. Instead, the Newberry issued the "Newberry Library Bulletin" which ran from 1944-1979. They also compiled Departmental Reports (NL Archives 03/20/21), which cover 1918-1961 in total. For Annual reports from 1962 to present, see NL Archives 03/20/20, Annual/Biennial Reports.