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U.S. Federal Documents: About

Northwestern University Libraries have been a U.S. Federal Depository Library since 1876. Our collection includes materials in paper, microfiche, CD-ROM, DVD formats and online formats. This guide is based on a similar guide by Kelly Smith at UCSD.

Northwestern University Libraries and the Federal Depository Library Program


"The Federal Depository Library Program (FDLP) was established by Congress to ensure that the American public has access to its Government's information. Since 1813, depository libraries have safeguarded the public's right to know by collecting, organizing, maintaining, preserving, and assisting users with information from the Federal Government. The FDLP provides Government information at no cost to designated depository libraries throughout the country and territories. These depository libraries, in turn, provide local, no-fee access to Government information in an impartial environment with professional assistance." (from FDLP Desktop)

Other depository libraries in Chicago include the Chicago Public Library (Harold Washington Library Center), DePaul University, Illinois Institute of Technology, Loyola University Chicago, Northern Illinois University, Northeastern Illinois University, University of Chicago, and many others.


Federal Depository Library Program Logo


Northwestern University Libraries (NUL) became a depository library in 1876. As a Federal Depository Library, we provide free access to and reference service for publications issued by the federal government.

The U.S. government issues a vast number of publications pertinent to almost all aspects of daily life and NUL selects those publications we believe to be of greatest use to our constituencies. NUL currently receives 75% of the publications distributed through the Federal Depository Library Program, creating an interdisciplinary collection with an emphasis on U.S. demographics, defense, business, economy, education, environment, public policy, legislation, health care, international trade, and foreign relations.  These items come in various formats, including print volumes, microfiche, CD/DVD, and online.

Most of our government documents are located in Room B190 on the lower level of the University Library. Some documents are housed offsite at the Oak Grove Library Center in Waukegan and may be requested for delivery to NU libraries in Evanston or Chicago using NUSearch. Call numbers for government documents published after 1976 may be found by using NUSearch and most items may be checked out.  Since a significant proportion of the collection is not yet represented in NUSearch, contact library staff at


Unlike most print resources in the library, which are classified with the Dewey Decimal or Library of Congress call number systems, U.S. federal government publications are arranged by the Superintendent of Documents (SuDocs) call number system. The SuDocs system is a provenance arrangement—publications are organized by the issuing agency. So, A call numbers are for the Department of Agriculture, C is Commerce, D is Defense, and so on. There are, of course, exceptions to the straightforward letters: X and Y are used for various Congressional publications.

SuDocs numbers do not read as a decimal, the way Dewey and LC numbers do. Instead, the numbers before and after the dot are whole numbers. So, while D 19.18 would come before D 19.3 in LC order (because it reads as eight), it comes after D 19.3 in SuDocs order (because it reads as 19.eighteen). See MSU's SuDocs Basics for more guidance.

A very basic break-down of a SuDocs number:

  • I 49.10:999 
  • First letter indicates issuing department (I=Department of the Interior)
  • First whole number before the dot indicates a subordinate office within that department (49=Fish & Wildlife Service)
  • First whole number after the dot indicates a category of publication, series, or serial title (10=directories)
  • Numbers or letters and numbers after the colon represent individual publications, years, issues or editions (pub date=1999)

Public access to documents received through the FDLP is guaranteed by U.S. law. Please see the Library's policies covering Building Access, Building Use, and Public Computers for general information or contact Anne Zald, U.S. Government Information Librarian, with specific questions regarding the federal documents collection.

The majority of government publications at the NULibraries are housed in the University Library on the Lower Level, Room B190 (additional maps of the University Library). Material in B190 are in various formats, e.g. print, microfiche, CD, DVD, and VHS tapes.

Some government publications are stored off-site in the Oak Grove Library Center which will be indicated in NUSearch.

Research Help

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Anne Zald
Anne Zald
Subjects: Government Information; Gender & Sexuality Studies; Social Science Data; Regulatory Compliance
Main Library Room 1214
Northwestern University Library
1970 Campus Drive
Evanston, IL 60208
Skype Contact: anne.zald
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